List of Contaminants

Our curated package for home inspectors and service professionals tests for 100+ contaminants. Here you'll find them all organized by primary concern for your customer. Whether it's for health or for home, you'll find it here.

Home Concerns

Alkalinity (as CaCO3)

Method: SM 2320 B

Definition: Capacity to neutralize acids, mainly from bicarbonate.

Source: Dissolved carbonate minerals in groundwater.

Impact: Stabilizes pH, preventing pipe corrosion or scaling in appliances and plumbing.

Unit: PPM

Normal Range: 20–200

Standard: No EPA MCL; typical range 20–200 mg/L for pH stability

Source Link: EPA

Bicarbonate

Method: SM 2320 B

Definition: A component of alkalinity, contributing to pH buffering.

Source: Dissolved carbonate minerals in groundwater.

Impact: Reduces corrosivity, protecting pipes and appliances from scaling or damage.

Unit: PPM

Normal Range: 20–200

Standard: No EPA MCL; typically 20–200 mg/L for water stability

Source Link: EPA

Calcium

Method: EPA 200.7

Definition: An essential mineral contributing to hardness.

Source: Dissolved from limestone or dolomite.

Impact: Leads to scale buildup in pipes and appliances, reducing efficiency.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL; typical range 10–100 mg/L for hardness

Source Link: EPA

Carbonate

Method: SM 2320 B

Definition: A component of alkalinity, contributing to pH buffering at higher pH levels.

Source: Dissolved carbonate minerals in groundwater.

Impact: Contributes to scaling in pipes and appliances at high pH; affects water stability.

Unit: PPM

Normal Range: 0–50

Standard: No EPA MCL; typically low in neutral pH water

Source Link: EPA

Chloride

Method: EPA 300.0

Definition: A naturally occurring ion in water.

Source: Natural salts, seawater intrusion, or road de-icing salts.

Impact: High levels cause salty taste and can corrode pipes and fixtures.

Unit: PPM

Normal Range: 0–250

Standard: EPA Secondary MCL: 250 mg/L (aesthetic)

Source Link: EPA

Chloride-to-Sulfate Mass Ratio

Method: Calculated (EPA 300.0 for Chloride and Sulfate)

Definition: Ratio of chloride to sulfate concentrations in water.

Source: Natural minerals, runoff, or industrial inputs.

Impact: High ratios indicate corrosion potential in pipes; affects water treatment decisions.

Unit: Unitless

Normal Range: 0.5–2.0

Standard: No EPA MCL; used in corrosion control assessments

Source Link: EPA

Chlorine Strip

Method: Colorimetric Test Strip (e.g., EPA-approved kits)

Definition: Measures residual chlorine from water disinfection.

Source: Added during water treatment to kill pathogens.

Impact: High levels cause unpleasant taste/odor and may irritate appliances; low levels reduce disinfection efficacy.

Unit: PPM

Normal Range: 0–4

Standard: EPA MCL: 4 mg/L

Source Link: EPA

Conductivity

Method: EPA 120.1

Definition: A measure of water’s ability to conduct electricity due to ions.

Source: Dissolved salts or minerals in water.

Impact: Indicates water quality; high levels can cause scaling or corrosion in appliances.

Unit: µS/cm

Normal Range: 50–1500

Standard: No EPA MCL; typical range 50–1500 µS/cm for potable water

Source Link: EPA

Grains per gallon

Method: Calculated (SM 2340 B for Hardness)

Definition: A unit of water hardness, equivalent to mg/L divided by 17.1.

Source: Dissolved calcium and magnesium from minerals.

Impact: High levels cause scaling in pipes and appliances, reducing efficiency; affects soap lathering.

Unit: gpg

Normal Range: 0–23

Standard: No EPA MCL; typically 0–23 gpg (soft to very hard)

Source Link: EPA

Hardness

Method: SM 2340 B

Definition: A measure of total calcium and magnesium ions in water.

Source: Dissolved minerals from limestone or dolomite.

Impact: Causes scale buildup in pipes, appliances, and fixtures; affects soap lathering.

Unit: PPM

Normal Range: 0–400

Standard: No EPA MCL; typical range 0–400 mg/L (soft to very hard)

Hard Water Details: ≤ 60 is considered soft, 61 to 120 is moderately hard, 121 to 180 is hard, >180 is very hard

Source Link: USGS

Hardness (Ca Mg)

Method: SM 2340 B

Definition: Hardness specifically from calcium and magnesium ions.

Source: Dissolved minerals from limestone or dolomite.

Impact: Contributes to scaling in pipes and appliances; affects water softener design.

Unit: PPM

Normal Range: 0–400

Standard: No EPA MCL; typically aligned with total hardness (0–400 mg/L)

Hard Water Details: ≤ 60 mg/L is considered soft, 61 to 120 is moderately hard, 121 to 180 is hard, >180 is very hard

Source Link: USGS

Hardness (Total)

Method: SM 2340 B

Definition: Total concentration of calcium and magnesium ions, expressed as CaCO3.

Source: Dissolved minerals from geological formations.

Impact: Causes scaling in pipes and appliances; impacts soap efficiency and water taste.

Unit: PPM

Normal Range: 0–400

Standard: No EPA MCL; typical range 0–400 mg/L (soft to very hard)

Hard Water Details: ≤ 60 mg/L is considered soft, 61 to 120 is moderately hard, 121 to 180 is hard, >180 is very hard

Source Link: USGS

Iron

Method: EPA 200.7

Definition: A naturally occurring metal in water.

Source: Natural deposits, corroding pipes, or industrial runoff.

Impact: Causes red-brown staining on fixtures, laundry, and pipes; affects water taste.

Unit: PPM

Normal Range: 0–0.3

Standard: EPA Secondary MCL: 0.3 mg/L (aesthetic)

Source Link: EPA

Langelier Saturation Index

Method: Calculated (based on pH, alkalinity, calcium, temperature, TDS)

Definition: A calculated index assessing water’s tendency to corrode or scale.

Source: Derived from water chemistry parameters.

Impact: Negative values indicate corrosive water; positive values indicate scaling potential, affecting pipes and appliances.

Unit: Unitless

Normal Range: -2 to +2

Standard: No EPA MCL; ideal range -0.5 to +0.5 for balanced water

Source Link: EPA

Magnesium

Method: EPA 200.7

Definition: A mineral contributing to water hardness.

Source: Dissolved from dolomite or other minerals.

Impact: Causes scaling in appliances and pipes; affects water taste.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL; typical range 5–50 mg/L for hardness

Source Link: EPA

Method: EPA 150.1

Definition: A measure of water’s acidity or alkalinity.

Source: Natural minerals, atmospheric CO2, or industrial inputs.

Impact: Low pH (acidic) corrodes pipes; high pH (alkaline) causes scaling.

Unit: pH units

Normal Range: 6.5–8.5

Standard: EPA Secondary MCL: 6.5–8.5 (aesthetic)

Source Link: EPA

Phosphorus

Method: EPA 365.1

Definition: A nutrient often present as phosphate in water.

Source: Agricultural runoff, fertilizers, or detergents.

Impact: High levels promote algae growth, affecting water quality and appliance efficiency.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL; typically <0.1 mg/L to prevent eutrophication

Source Link: EPA

Potassium

Method: EPA 200.7

Definition: A mineral found in water.

Source: Natural minerals or agricultural runoff.

Impact: High levels can impart a bitter taste and affect appliance efficiency.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL; typical range 1–10 mg/L

Source Link: EPA

Silica

Method: EPA 200.7

Definition: A compound of silicon and oxygen in water.

Source: Natural minerals or geological formations.

Impact: Contributes to scaling in appliances and pipes at high levels.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL; typical range 5–50 mg/L

Source Link: EPA

Sodium

Method: EPA 200.7

Definition: A mineral ion in water.

Source: Natural salts, road salt, or water softeners.

Impact: High levels impart a salty taste; may affect appliances or taste perception.

Unit: PPM

Normal Range: No MCL

Standard: EPA Health Advisory: 20 mg/L for low-sodium diets

Source Link: EPA

Sodium Adsorption Ratio

Method: Calculated (based on sodium, calcium, magnesium)

Definition: A ratio assessing sodium’s impact on soil permeability in irrigation water.

Source: Derived from sodium, calcium, and magnesium concentrations.

Impact: High ratios can affect water suitability for irrigation, impacting appliance use in agricultural settings.

Unit: Unitless

Normal Range: 0–9

Standard: No EPA MCL; typically <9 for irrigation suitability

Source Link: EPA

Total Dissolved Solids

Method: SM 2540 C

Definition: Total amount of dissolved minerals and salts in water.

Source: Natural minerals, runoff, or industrial discharge.

Impact: High levels cause taste issues and scaling in pipes and appliances.

Unit: PPM

Normal Range: 0–500

Standard: EPA Secondary MCL: 500 mg/L (aesthetic)

Source Link: EPA

Health Concerns

1,1 Dichloroethane

Method: EPA 524.2

Definition: A volatile organic compound used in industrial solvents.

Source: Industrial discharge or chemical spills.

Impact: Potential liver and kidney damage; limited evidence of carcinogenicity.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,1 Dichloroethylene

Method: EPA 524.2

Definition: A volatile organic compound used in plastics production.

Source: Industrial runoff or improper disposal.

Impact: Causes liver damage; potential carcinogen.

Unit: PPB

Normal Range: 0–7

Standard: EPA MCL: 7 µg/L

Source Link: EPA

1,1 Dichloropropene

Method: EPA 524.2

Definition: A volatile organic compound in pesticides.

Source: Agricultural runoff or industrial discharge.

Impact: Potential respiratory and liver effects; limited health data.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,1,1 Trichloroethane

Method: EPA 524.2

Definition: A volatile organic compound used as a solvent.

Source: Industrial discharge or degreasing operations.

Impact: Causes nervous system effects; low risk at regulated levels.

Unit: PPB

Normal Range: 0–200

Standard: EPA MCL: 200 µg/L

Source Link: EPA

1,1,1,2 Tetrachloroethane

Method: EPA 524.2

Definition: A volatile organic compound in industrial solvents.

Source: Industrial runoff or chemical spills.

Impact: Potential liver and nervous system damage; limited data.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,1,2 Trichloroethane

Method: EPA 524.2

Definition: A volatile organic compound used in solvents.

Source: Industrial discharge or improper disposal.

Impact: Causes liver and kidney damage; potential carcinogen.

Unit: PPB

Normal Range: 0–5

Standard: EPA MCL: 5 µg/L

Source Link: EPA

1,1,2,2 Tetrachloroethane

Method: EPA 524.2

Definition: A volatile organic compound used in industrial processes.

Source: Industrial runoff or chemical spills.

Impact: Causes liver damage; potential carcinogen.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,2 Dichlorobenzene

Method: EPA 524.2

Definition: A volatile organic compound used in solvents and pesticides.

Source: Industrial discharge or agricultural runoff.

Impact: Causes liver and kidney damage; potential endocrine disruptor.

Unit: PPB

Normal Range: 0–600

Standard: EPA MCL: 600 µg/L

Source Link: EPA

1,2 Dichloroethane

Method: EPA 524.2

Definition: A volatile organic compound used in chemical synthesis.

Source: Industrial runoff or improper disposal.

Impact: Carcinogen; causes liver and kidney damage.

Unit: PPB

Normal Range: 0–5

Standard: EPA MCL: 5 µg/L

Source Link: EPA

1,2 Dichloropropane

Method: EPA 524.2

Definition: A volatile organic compound used in pesticides and solvents.

Source: Agricultural runoff or industrial discharge.

Impact: Causes liver and kidney damage; potential carcinogen.

Unit: PPB

Normal Range: 0–5

Standard: EPA MCL: 5 µg/L

Source Link: EPA

1,2,3 Trichlorobenzene

Method: EPA 524.2

Definition: A volatile organic compound used in chemical manufacturing.

Source: Industrial discharge or improper disposal.

Impact: Limited health data; may cause liver and kidney effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,2,3 Trichloropropane

Method: EPA 524.2

Definition: A volatile organic compound in industrial solvents.

Source: Industrial runoff or pesticide residues.

Impact: Carcinogen; causes liver and kidney damage.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL; California MCL: 0.005 µg/L

Source Link: CA Water Board

1,2,4 Trichlorobenzene

Method: EPA 524.2

Definition: A volatile organic compound used in dyes and pesticides.

Source: Industrial discharge or agricultural runoff.

Impact: Causes liver and kidney damage; potential endocrine disruptor.

Unit: PPB

Normal Range: 0–70

Standard: EPA MCL: 70 µg/L

Source Link: EPA

1,2,4 Trimethylbenzene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline or industrial solvents.

Impact: May cause respiratory irritation; limited health data.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,3 Dichlorobenzene

Method: EPA 524.2

Definition: A volatile organic compound in chemical manufacturing.

Source: Industrial discharge or improper disposal.

Impact: Limited health data; may cause liver and kidney effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,3 Dichloropropane

Method: EPA 524.2

Definition: A volatile organic compound in solvents.

Source: Industrial runoff or chemical spills.

Impact: Limited health data; may cause respiratory and liver effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,3 Dichloropropene

Method: EPA 524.2

Definition: A volatile organic compound in pesticides.

Source: Agricultural runoff or improper disposal.

Impact: Potential carcinogen; causes respiratory irritation.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,3,5 Trimethylbenzene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline or industrial solvents.

Impact: May cause respiratory irritation; limited health data.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

1,4 Dichlorobenzene

Method: EPA 524.2

Definition: A volatile organic compound used in mothballs and deodorants.

Source: Industrial discharge or household products.

Impact: Causes liver and kidney damage; potential carcinogen.

Unit: PPB

Normal Range: 0–75

Standard: EPA MCL: 75 µg/L

Source Link: EPA

2,2 Dichloropropane

Method: EPA 524.2

Definition: A volatile organic compound in solvents.

Source: Industrial runoff or chemical spills.

Impact: Limited health data; may cause liver and kidney effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Antimony

Method: EPA 200.8

Definition: A toxic metalloid in water.

Source: Mining, industrial runoff, or natural deposits.

Impact: Causes nausea, vomiting, and potential carcinogenic effects.

Unit: PPM

Normal Range: 0–0.006

Standard: EPA MCL: 0.006 mg/L

Source Link: EPA

Arsenic

Method: EPA 200.8

Definition: A toxic metalloid in water.

Source: Natural deposits, mining, or agricultural runoff.

Impact: Causes skin lesions, cancer, and cardiovascular issues.

Unit: PPM

Normal Range: 0–0.01

Standard: EPA MCL: 0.01 mg/L

Source Link: EPA

Barium

Method: EPA 200.8

Definition: A metal found in water.

Source: Natural deposits or industrial discharge.

Impact: Causes hypertension and cardiovascular issues at high levels.

Unit: PPM

Normal Range: 0–2

Standard: EPA MCL: 2 mg/L

Source Link: EPA

Benzene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline, industrial discharge, or leaks.

Impact: Carcinogen; causes leukemia and anemia.

Unit: PPB

Normal Range: 0–5

Standard: EPA MCL: 5 µg/L

Source Link: EPA

Beryllium

Method: EPA 200.8

Definition: A toxic metal in water.

Source: Industrial runoff or natural deposits.

Impact: Causes lung cancer and bone disease with chronic exposure.

Unit: PPM

Normal Range: 0–0.004

Standard: EPA MCL: 0.004 mg/L

Source Link: EPA

Boron

Method: EPA 200.7

Definition: A metalloid in water.

Source: Natural deposits, fertilizers, or industrial runoff.

Impact: High levels may cause reproductive and developmental issues.

Unit: PPM

Normal Range: No MCL

Standard: WHO Guideline: 2.4 mg/L; no EPA MCL

Source Link: WHO

Bromobenzene

Method: EPA 524.2

Definition: A volatile organic compound used in chemical synthesis.

Source: Industrial discharge or chemical spills.

Impact: Limited health data; may cause liver and nervous system effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Bromochloromethane

Method: EPA 524.2

Definition: A volatile organic compound, often a disinfection byproduct.

Source: Water treatment processes or industrial discharge.

Impact: Limited health data; may cause liver and kidney effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Bromodichloromethane

Method: EPA 524.2

Definition: A trihalomethane formed during water chlorination.

Source: Water treatment processes.

Impact: Potential carcinogen; causes liver and kidney damage.

Unit: PPB

Normal Range: 0–80 (as part of Total THMs)

Standard: EPA MCL: 80 µg/L (Total THMs)

Source Link: EPA

Bromoform

Method: EPA 524.2

Definition: A trihalomethane formed during water chlorination.

Source: Water treatment processes.

Impact: Potential carcinogen; causes liver and nervous system effects.

Unit: PPB

Normal Range: 0–80 (as part of Total THMs)

Standard: EPA MCL: 80 µg/L (Total THMs)

Source Link: EPA

Bromomethane

Method: EPA 524.2

Definition: A volatile organic compound used in pesticides.

Source: Agricultural runoff or industrial discharge.

Impact: Causes nervous system and lung damage; potential carcinogen.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Cadmium

Method: EPA 200.8

Definition: A toxic heavy metal in water.

Source: Industrial discharge, mining, or corroding pipes.

Impact: Causes kidney damage and bone disease; potential carcinogen.

Unit: PPM

Normal Range: 0–0.005

Standard: EPA MCL: 0.005 mg/L

Source Link: EPA

Carbon Tetrachloride

Method: EPA 524.2

Definition: A volatile organic compound used in solvents.

Source: Industrial discharge or chemical spills.

Impact: Carcinogen; causes liver and kidney damage.

Unit: PPB

Normal Range: 0–5

Standard: EPA MCL: 5 µg/L

Source Link: EPA

Chlorine

Method: EPA 300.0

Definition: A disinfectant added to water to kill pathogens.

Source: Water treatment processes.

Impact: High levels cause eye and respiratory irritation; forms harmful byproducts like THMs.

Unit: PPM

Normal Range: 0–4

Standard: EPA MCL: 4 mg/L

Source Link: EPA

Chlorobenzene

Method: EPA 524.2

Definition: A volatile organic compound used in solvents.

Source: Industrial discharge or chemical spills.

Impact: Causes liver and kidney damage; low risk at regulated levels.

Unit: PPB

Normal Range: 0–100

Standard: EPA MCL: 100 µg/L

Source Link: EPA

Chloroethane

Method: EPA 524.2

Definition: A volatile organic compound used in chemical synthesis.

Source: Industrial discharge or chemical spills.

Impact: Limited health data; may cause nervous system effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Chloroform

Method: EPA 524.2

Definition: A trihalomethane formed during water chlorination.

Source: Water treatment processes.

Impact: Potential carcinogen; causes liver and kidney damage.

Unit: PPB

Normal Range: 0–80 (as part of Total THMs)

Standard: EPA MCL: 80 µg/L (Total THMs)

Source Link: EPA

Chloromethane

Method: EPA 524.2

Definition: A volatile organic compound used in chemical production.

Source: Industrial discharge or natural sources.

Impact: Limited health data; may cause nervous system effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Chlorotoluene 2

Method: EPA 524.2

Definition: A volatile organic compound (2-chlorotoluene) used in chemical synthesis.

Source: Industrial discharge or chemical spills.

Impact: Limited health data; may cause respiratory and liver effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Chlorotoluene 4

Method: EPA 524.2

Definition: A volatile organic compound (4-chlorotoluene) used in chemical synthesis.

Source: Industrial discharge or chemical spills.

Impact: Limited health data; may cause respiratory and liver effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Chromium (Total)

Method: EPA 200.8

Definition: A metal including both trivalent and hexavalent forms.

Source: Industrial runoff or natural deposits.

Impact: Hexavalent chromium is a carcinogen; causes lung and digestive issues.

Unit: PPM

Normal Range: 0–0.1

Standard: EPA MCL: 0.1 mg/L

Source Link: EPA

cis 1,2 Dichloroethylene

Method: EPA 524.2

Definition: A volatile organic compound from industrial solvents.

Source: Industrial runoff or chemical spills.

Impact: Causes liver and kidney damage; more toxic than trans isomer.

Unit: PPB

Normal Range: 0–70

Standard: EPA MCL: 70 µg/L

Source Link: EPA

Cobalt

Method: EPA 200.8

Definition: A trace metal in water.

Source: Natural deposits or industrial runoff.

Impact: High levels may cause heart and thyroid issues; limited data.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL; WHO suggests <0.01 mg/L

Source Link: WHO

Cyanide

Method: EPA 335.4

Definition: A toxic chemical compound in water.

Source: Industrial discharge, mining, or chemical spills.

Impact: Causes nerve damage and thyroid issues; highly toxic at elevated levels.

Unit: PPM

Normal Range: 0–0.2

Standard: EPA MCL: 0.2 mg/L

Source Link: EPA

Dibromochloromethane

Method: EPA 524.2

Definition: A trihalomethane formed during water chlorination.

Source: Water treatment processes.

Impact: Potential carcinogen; causes liver and kidney damage.

Unit: PPB

Normal Range: 0–80 (as part of Total THMs)

Standard: EPA MCL: 80 µg/L (Total THMs)

Source Link: EPA

Dibromochloropropane

Method: EPA 524.2

Definition: A volatile organic compound used in pesticides.

Source: Agricultural runoff or historical pesticide use.

Impact: Carcinogen; causes reproductive and liver damage.

Unit: PPB

Normal Range: 0–0.2

Standard: EPA MCL: 0.2 µg/L

Source Link: EPA

Dibromomethane

Method: EPA 524.2

Definition: A volatile organic compound used in chemical synthesis.

Source: Industrial discharge or water treatment byproducts.

Impact: Limited health data; may cause liver and kidney effects.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Dichlorodifluoromethane

Method: EPA 524.2

Definition: A volatile organic compound used as a refrigerant.

Source: Industrial leaks or historical use.

Impact: Low toxicity; may cause dizziness at high levels.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Dichloromethane

Method: EPA 524.2

Definition: A volatile organic compound used as a solvent.

Source: Industrial discharge or paint strippers.

Impact: Potential carcinogen; causes liver and lung effects.

Unit: PPB

Normal Range: 0–5

Standard: EPA MCL: 5 µg/L

Source Link: EPA

Dieldrin

Method: EPA 508

Definition: A chlorinated pesticide, now banned but persistent in the environment.

Source: Agricultural runoff or historical pesticide use.

Impact: Carcinogen; causes liver and nervous system damage.

Unit: PPB

Normal Range: 0–0.002

Standard: EPA MCL: 0.002 µg/L

Source Link: EPA

E. coli

Method: SM 9223B

Definition: A fecal indicator bacterium.

Source: Sewage, animal waste, or runoff.

Impact: Indicates fecal contamination; causes gastrointestinal illness.

Unit: P/A

Normal Range: Absence

Standard: EPA MCL: 0 (absence)

Source Link: EPA

Endrin

Method: EPA 508

Definition: A banned organochlorine pesticide, persistent in the environment.

Source: Agricultural runoff or historical pesticide use.

Impact: Causes nervous system damage and potential liver effects.

Unit: PPB

Normal Range: 0–2

Standard: EPA MCL: 2 µg/L

Source Link: EPA

Ethylbenzene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline, industrial discharge, or leaks.

Impact: Causes liver and kidney damage; low risk at regulated levels.

Unit: PPB

Normal Range: 0–700

Standard: EPA MCL: 700 µg/L

Source Link: EPA

Ethylene dibromide

Method: EPA 504.1

Definition: A volatile organic compound used in pesticides and fuel additives.

Source: Agricultural runoff or fuel spills.

Impact: Carcinogen; causes liver and kidney damage.

Unit: PPB

Normal Range: 0–0.05

Standard: EPA MCL: 0.05 µg/L

Source Link: EPA

Fluoride

Method: EPA 300.0

Definition: A mineral added to water for dental health or naturally occurring.

Source: Water treatment or natural deposits.

Impact: Low levels prevent tooth decay; high levels cause dental/skeletal fluorosis.

Unit: PPM

Normal Range: 0–4

Standard: EPA MCL: 4 mg/L

Source Link: EPA

Hexachlorobutadiene

Method: EPA 524.2

Definition: A volatile organic compound used in industrial processes.

Source: Industrial discharge or chemical spills.

Impact: Potential carcinogen; causes kidney and liver damage.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Isopropylbenzene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline or industrial solvents.

Impact: Limited health data; may cause respiratory irritation.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Lithium

Method: EPA 200.7

Definition: A naturally occurring alkali metal in water.

Source: Natural deposits or industrial runoff.

Impact: Limited health data; high levels may affect thyroid and kidney function.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

m,p Xylene

Method: EPA 524.2

Definition: Volatile organic compounds in petroleum products.

Source: Gasoline, paint, or industrial solvents.

Impact: Causes nervous system effects, dizziness; low health risk at typical levels.

Unit: PPB

Normal Range: 0–10000 (as part of total xylenes)

Standard: EPA MCL for total xylenes: 10,000 µg/L

Source Link: EPA

Mercury

Method: EPA 245.1

Definition: A toxic heavy metal in water.

Source: Industrial discharge, mining, or natural deposits.

Impact: Causes neurological and kidney damage; highly toxic.

Unit: PPM

Normal Range: 0–0.002

Standard: EPA MCL: 0.002 mg/L

Source Link: EPA

Molybdenum

Method: EPA 200.8

Definition: A trace metal in water.

Source: Natural deposits or industrial runoff.

Impact: High levels may cause gout-like symptoms; limited health data.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL; WHO suggests <0.07 mg/L

Source Link: WHO

n Butylbenzene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline or industrial solvents.

Impact: Limited health data; may cause respiratory irritation.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

n Propylbenzene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline or industrial solvents.

Impact: Limited health data; may cause respiratory irritation.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Naphthalene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum and coal tar.

Source: Industrial discharge, mothballs, or fuel spills.

Impact: Causes hemolytic anemia and potential cancer risk with exposure.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL; WHO suggests <100 µg/L for taste/odor

Source Link: WHO

Nickel

Method: EPA 200.8

Definition: A metal in water.

Source: Industrial processes or natural deposits.

Impact: May cause skin irritation or lung issues at high levels; low toxicity in water.

Unit: PPM

Normal Range: No MCL

Standard: EPA Health Advisory: 0.1 mg/L (unregulated)

Source Link: EPA

Nitrate (as N #1)

Method: EPA 300.0

Definition: A nitrogen compound from fertilizers or sewage.

Source: Agricultural runoff, septic systems, or industrial discharge.

Impact: Causes methemoglobinemia (blue baby syndrome) in infants; potential cancer risk.

Unit: PPM

Normal Range: 0–10

Standard: EPA MCL: 10 mg/L

Source Link: EPA

Nitrite (as N #2)

Method: EPA 300.0

Definition: A nitrogen compound, often a byproduct of nitrate reduction.

Source: Agricultural runoff, septic systems, or industrial discharge.

Impact: Causes methemoglobinemia in infants; more toxic than nitrate.

Unit: PPM

Normal Range: 0–1

Standard: EPA MCL: 1 mg/L

Source Link: EPA

o Xylene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline, paint, or industrial solvents.

Impact: Causes nervous system effects, dizziness; low health risk at typical levels.

Unit: PPB

Normal Range: 0–10000 (as part of total xylenes)

Standard: EPA MCL for total xylenes: 10,000 µg/L

Source Link: EPA

p Isopropyltoluene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline or industrial solvents.

Impact: Limited health data; may cause respiratory irritation.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

sec Butylbenzene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline or industrial solvents.

Impact: Limited health data; may cause respiratory irritation.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Selenium

Method: EPA 200.8

Definition: A trace element in water.

Source: Natural deposits, mining, or industrial runoff.

Impact: Causes hair/nail loss, liver damage at high levels; essential in trace amounts.

Unit: PPM

Normal Range: 0–0.05

Standard: EPA MCL: 0.05 mg/L

Source Link: EPA

Silver

Method: EPA 200.8

Definition: A metal in water, sometimes used as a disinfectant.

Source: Industrial discharge or natural deposits.

Impact: Causes argyria (skin discoloration); low health risk at regulated levels.

Unit: PPM

Normal Range: 0–0.1

Standard: EPA Secondary MCL: 0.1 mg/L (aesthetic)

Source Link: EPA

Strontium

Method: EPA 200.8

Definition: A metal naturally occurring in water.

Source: Natural deposits or industrial runoff.

Impact: High levels may affect bone health; limited health data.

Unit: PPM

Normal Range: No MCL

Standard: EPA Health Advisory: 4 mg/L (unregulated)

Source Link: EPA

Styrene

Method: EPA 524.2

Definition: A volatile organic compound used in plastics production.

Source: Industrial discharge or leaching from plastics.

Impact: Causes liver and nervous system effects; potential carcinogen.

Unit: PPB

Normal Range: 0–100

Standard: EPA MCL: 100 µg/L

Source Link: EPA

tert Butylbenzene

Method: EPA 524.2

Definition: A volatile organic compound in petroleum products.

Source: Gasoline or industrial solvents.

Impact: Limited health data; may cause respiratory irritation.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Tetrachloroethylene

Method: EPA 524.2

Definition: A volatile organic compound used in dry cleaning and solvents.

Source: Industrial discharge or improper disposal.

Impact: Carcinogen; causes liver and nervous system damage.

Unit: PPB

Normal Range: 0–5

Standard: EPA MCL: 5 µg/L

Source Link: EPA

Thallium

Method: EPA 200.8

Definition: A toxic heavy metal in water.

Source: Mining, industrial runoff, or natural deposits.

Impact: Causes hair loss, kidney, and neurological damage.

Unit: PPM

Normal Range: 0–0.002

Standard: EPA MCL: 0.002 mg/L

Source Link: EPA

Tin

Method: EPA 200.8

Definition: A metal in water, sometimes from industrial processes.

Source: Industrial runoff or corroding tin pipes.

Impact: Low toxicity; limited health data at typical levels.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL; WHO suggests <0.1 mg/L

Source Link: WHO

Titanium

Method: EPA 200.8

Definition: A metal in water from natural or industrial sources.

Source: Industrial runoff or natural deposits.

Impact: Low toxicity; limited health data in drinking water.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Toluene Petroleum Compounds

Method: EPA 524.2

Definition: A volatile organic compound in gasoline and solvents.

Source: Fuel spills, industrial discharge, or petroleum refining.

Impact: Causes nervous system effects, dizziness; low risk at regulated levels.

Unit: PPB

Normal Range: 0–1000

Standard: EPA MCL: 1000 µg/L

Source Link: EPA

Total Coliform

Method: SM 9223B

Definition: A group of bacteria indicating water contamination.

Source: Environmental contamination, sewage, or runoff.

Impact: Indicates potential presence of pathogens; may cause gastrointestinal illness.

Unit: P/A

Normal Range: Absence

Standard: EPA MCL: 0 (absence)

Source Link: EPA

Total THMs

Method: EPA 524.2

Definition: Total trihalomethanes (chloroform, bromodichloromethane, dibromochloromethane, bromoform).

Source: Water treatment processes (chlorination).

Impact: Potential carcinogens; cause liver and kidney damage.

Unit: PPB

Normal Range: 0–80

Standard: EPA MCL: 80 µg/L

Source Link: EPA

trans 1,3 Dichloropropene

Method: EPA 524.2

Definition: A volatile organic compound in pesticides.

Source: Agricultural runoff or improper disposal.

Impact: Potential carcinogen; causes respiratory irritation.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Trichloroethylene

Method: EPA 524.2

Definition: A volatile organic compound used in degreasing.

Source: Industrial discharge or improper disposal.

Impact: Carcinogen; causes liver and nervous system damage.

Unit: PPB

Normal Range: 0–5

Standard: EPA MCL: 5 µg/L

Source Link: EPA

Trichlorofluoromethane

Method: EPA 524.2

Definition: A volatile organic compound used as a refrigerant.

Source: Industrial leaks or historical use.

Impact: Low toxicity; may cause dizziness at high levels.

Unit: PPB

Normal Range: No MCL

Standard: No EPA MCL

Source Link: EPA

Uranium

Method: EPA 200.8

Definition: A radioactive element in water.

Source: Natural deposits, mining, or nuclear industry runoff.

Impact: Causes kidney damage and potential cancer risk from radiation.

Unit: PPB

Normal Range: 0–30

Standard: EPA MCL: 30 µg/L

Source Link: EPA

Vanadium

Method: EPA 200.8

Definition: A metal in water from natural or industrial sources.

Source: Natural deposits or industrial runoff.

Impact: Limited health data; may cause respiratory or kidney effects at high levels.

Unit: PPM

Normal Range: No MCL

Standard: No EPA MCL; EPA Health Advisory: 0.021 mg/L

Source Link: EPA

Vinyl Chloride

Method: EPA 524.2

Definition: A volatile organic compound used in PVC production.

Source: Industrial discharge or leaching from PVC pipes.

Impact: Carcinogen; causes liver damage and neurological effects.

Unit: PPB

Normal Range: 0–2

Standard: EPA MCL: 2 µg/L

Source Link: EPA

Health & Home Concerns

Aluminum

Method: EPA 200.8

Definition: A lightweight metal in water.

Source: Natural soils, mining, or water treatment (alum).

Impact: May cloud water and impart a metallic taste; high levels potentially linked to neurological concerns, though evidence is limited.

Unit: PPM

Normal Range: 0–0.2

Standard: EPA Secondary MCL: 0.05–0.2 mg/L (aesthetic)

Source Link: EPA

Copper

Method: EPA 200.8

Definition: An essential metal.

Source: Corroding pipes, mining, or industrial runoff.

Impact: Leaves blue-green stains on fixtures and can cause digestive upset or liver issues at elevated levels.

Unit: PPM

Normal Range: 0–1.3

Standard: EPA MCL: 1.3 mg/L (action level)

Source Link: EPA

Hydrogen Sulfide (H2S) Gas Strip

Method: Colorimetric Test Strip (e.g., EPA-approved kits)

Definition: A gas causing a rotten egg odor in water.

Source: Bacterial activity in groundwater or decaying organic matter.

Impact: Causes foul odor and taste; may corrode pipes and fixtures; low health risk but unpleasant.

Unit: PPM

Normal Range: 0–0.05

Standard: No EPA MCL; typically <0.05 mg/L for aesthetic quality

Source Link: EPA

Lead

Method: EPA 200.8

Definition: A toxic heavy metal.

Source: Old plumbing, solder, or industrial runoff.

Impact: Contributes to pipe corrosion and causes serious health effects, including neurological damage and developmental issues in children.

Unit: PPM

Normal Range: 0–0.015

Standard: EPA MCL: 0.015 mg/L (action level)

Source Link: EPA

Manganese

Method: EPA 200.8

Definition: A naturally occurring metal in water.

Source: Natural deposits, mining, or industrial runoff.

Impact: Causes black staining on fixtures and laundry; high levels may affect neurological health.

Unit: PPM

Normal Range: 0–0.05

Standard: EPA Secondary MCL: 0.05 mg/L (aesthetic)

Source Link: EPA

Methyl Tertiary Butyl Ether (MTBE)

Method: EPA 524.2

Definition: A volatile organic compound used as a gasoline additive.

Source: Leaking underground fuel storage tanks or spills.

Impact: Causes unpleasant taste and odor; potential carcinogen with chronic exposure.

Unit: PPB

Normal Range: 0–20

Standard: No EPA MCL; EPA Health Advisory: 20–40 µg/L (aesthetic/health)

Source Link: EPA

Sulfate

Method: EPA 300.0

Definition: A naturally occurring ion in water.

Source: Dissolved minerals, mining, or industrial runoff.

Impact: High levels cause a bitter taste and scaling in pipes; may have laxative effects.

Unit: PPM

Normal Range: 0–250

Standard: EPA Secondary MCL: 250 mg/L (aesthetic)

Source Link: EPA

Turbidity

Method: EPA 180.1

Definition: A measure of water cloudiness due to suspended particles.

Source: Soil runoff, erosion, or organic matter.

Impact: Affects water clarity and aesthetics; may harbor pathogens, increasing health risks.

Unit: NTU

Normal Range: 0–1

Standard: EPA MCL: <1 NTU (health-based)

Source Link: EPA

Zinc

Method: EPA 200.8

Definition: An essential metal in water.

Source: Corroding galvanized pipes or industrial runoff.

Impact: Causes metallic taste and cloudiness; high levels may cause digestive issues.

Unit: PPM

Normal Range: 0–5

Standard: EPA Secondary MCL: 5 mg/L (aesthetic)

Source Link: EPA