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EWG Statement, 03/10/2008

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NATIONAL SUMMARY

Quality Varies Across the U.S.

CONTAMINANTS DATABASE

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Tap Water Quality Report The State of Illinois 1,820 Water Systems Serving 11,416,269 People

An Environmental Working Group analysis of tap water tests from 1998 through 2003 for 1,820 communities across Illinois shows 90 pollutants were found in drinking water across the state.

Pollution Summary

90 58	28 15	18 14	58 38	18 14	23 15
Total pollutants	Agricultural pollutants	Sprawl and Urban pollutants	Industrial pollutants	Water Treatment and Distribution Byproducts	Naturally occurring pollutants
Number of pollutants detected (1998 - 2003)			Over health based limits

NOTE: Health based limits included in this analysis include enforceable drinking water limits (called Maximum Contaminant Limits, or MCLs) as well as governmental, non-enforceable health guidelines, such as Maximum Contaminant Limit Goals (MCLGs), lifetime health advisory levels, one-day and ten-day advisory levels to protect children from non-cancer health endpoints, and other government-established health guidelines for tap water contaminants.

Health Summary

The federal government has set standards for 80 chemical pollutants in tap water, balancing health concerns and treatment costs.

Contaminants found in state tap water (1998-2003): 90

Total population exposed above health-based limits: 10,614,995

Communities served water with contaminants above health-based limits: 1,342

Health effects or target organs of contaminants found: Cardiovascular or Blood Toxicity, Cancer, Developmental Toxicity, Endocrine Toxicity, Immunotoxicity, Kidney Toxicity, Gastrointestinal or Liver Toxicity, Musculoskeletal Toxicity, Neurotoxicity, Reproductive Toxicity, Respiratory Toxicity, and Skin Sensitivity.

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Contaminants found above health based limits: 58

Rank	Contaminant Name	Population Exposed (of 11,416,269 Total)		Number of Water Systems (of 1,820) Total
		At Any Level	Above Health Limits See Note	With Detected	Above Health Limits See Note
1	Barium (total)	7,461,681	291,127	1179	38
		Mineral from drilling and mining waste runoff; erosion of natrual deposits
2	Sulfate	7,085,304	0	1006	0
		Substance from natural deposits, industrial processes, and agriculture
3	Total trihalomethanes (TTHMs)	10,105,574	9,214,604	971	747
		Measure of four disinfection by-products
4	Chloroform	10,021,447	8,501,183	935	641
		Disinfection by-product
5	Bromodichloromethane	9,823,992	9,454,491	832	783
		Disinfection by-product
6	Dibromochloromethane	9,634,273	9,125,347	777	715
		Disinfection by-product
7	Nitrate & nitrite	6,635,620	0	769	0
		Chemical that enters water from fertilizer runoff, leaching septic tanks, and erosion of natural deposits
8	Nitrate	6,528,995	149,709	744	16
		Chemical that enters water from fertilizer runoff, leaching septic tanks, and erosion of natural deposits
9	Total haloacetic acids	9,080,186	472,974	732	138
		Measure of disinfection by-products; refers to the sum of the concentrations of dichloroacetic acid, trichloroacetic acid, monochloroacetic acid, monobromoacetic acid and dibromoacetic acid in a water sample.
10	Dichloroacetic acid	8,867,182	6,395	697	3
		Disinfection by-product

View Full Table

NOTE: Health based limits included in this analysis include enforceable drinking water limits (called Maximum Contaminant Limits, or MCLs) as well as governmental, non-enforceable health guidelines, such as Maximum Contaminant Limit Goals (MCLGs), lifetime health advisory levels, one-day and ten-day advisory levels to protect children from non-cancer health endpoints, and other government-established health guidelines for tap water contaminants.

Testing Summary

The federal government has set standards for some of the pollutants found in tap water supplies.

Contaminants reported as tested by water suppliers in Illinois		147
	Contaminants tested due to federal law:	97
	Contaminants tested in addition to those required by federal law:	50

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Violations Summary

According to EPA, in 2003 6% of America's public water systems reported one or more violations of a health-based drinking water standard, and 26% reported significant violations of either monitoring and reporting requirements or health-based standards.

Reported violations (1998 - 2003): 4,823

Number of IL systems with violations: 1,025 (56.3%)

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Information on violations is drawn directly from EPA's national violations database in the Agency's Safe Drinking Water Information System. Analyses by others have raised questions about the quality of the information in EPA's database. For the purposes of this investigation, EWG is not showing below or including in our analyses, those violations for individual water suppliers that occurred on days for which the total number of violations assigned by EPA to that water supplier was greater than 20. This criteria was based on common characteristics of incorrect violations data as identified by water utilities, from a review of EPA's violations data by several hundred utilities prior to the release of EWG's investigation.