The Power of Information

National Drinking Water Database


Monterey Park-City, Water Dept. - Los Angeles, CA


Serves 57,000 people - Test data available: 2004-2009

This drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group (EWG) by the California Department of Public Health. It is part of EWG's national database that includes 47,667 drinking water utilities and 20 million test results. Water utilities nationwide detected more than 300 pollutants between 2004 and 2009. More than half of these chemicals are unregulated, legal in any amount. Despite this widespread contamination, the federal government invests few resources to protecting rivers, reservoirs, and groundwater from pollution in the first place. The information below summarizes test results for this utility and lists potential health concerns.

 
This Drinking Water System
National Average
Exceed Health GuidelinesTests showing chemicals at concentrations above health guidelines established by federal and state health agencies. These guidelines are typically set at a levels that pose no significant health risk.
14 chemicals
4
Health Standard ExceedencesChemicals detected at concentrations above the legal limit, the Maximum Contaminant Level (MCLs) established by the U.S. EPA. Most MCLs are based on annual averages, so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.
2 chemicals
0.5
Pollutants FoundThe total number of contaminants detected since 2004, according to data provided by the state water agency.
33 chemicals
8
Tests ConductedThe total number of number of water quality tests conducted by water utilities and recorded in data provided by the state water agency.
314,146 tests
420

Contaminants Exceeding Health Guidelines

ContaminantAverage/
Maximum
Result
Health Limit
Exceeded
Legal Limit
Exceeded

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
Arsenic (total)Arsenic contaminates drinking water due to mining runoff, erosion of natural deposits, emissions from glass and electronics processing and the use of arsenical compounds as wood preservatives and pesticides.2.01 ppb
15 ppb
Yes
MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb
Yes
10 ppb
AluminumAluminum is a metal released from metal refineries and mining operations.17.71 ppb
325 ppb
Yes
200 ppb
Yes
200 ppb
TetrachloroethyleneTetrachloroethylene (perc) is a common soil and groundwater contaminant used in dry cleaning and as a solvent in automotive and metalworking factories and other industries.0.25 ppb
2.58 ppb
Yes
MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb
No
5 ppb
TrichloroethyleneTrichloroethylene is used to remove grease from fabricated metal parts and in the production of some textiles; this pollutant comes from metal degreasing sites, metal finishing and rubber processing industries.0.09 ppb
0.78 ppb
Yes
MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb
No
5 ppb
Alpha particle activityAlpha particles are a form of radiation released from mining waste pollutants and natural sources.3.82 pCi/L
14.1 pCi/L
Yes
MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 pCi/L
No
15 pCi/L
Radium-228Radium-228 is a radioactive element usually found around uranium deposits.0.67 pCi/L
4.4 pCi/L
Yes
MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 pCi/L
No
5 pCi/L
Combined Radium (-226 & -228)Radium is a radioactive element usually found around uranium deposits.0.79 pCi/L
4.4 pCi/L
Yes
MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 pCi/L
No
5 pCi/L
1,2,3-Trichloropropane1,2,3-Trichloropropane is an industrial solvent, degreasing agent, and paint and varnish remover.<0.01 ppb
<0.01 ppb
Yes
<0.01 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
PerchloratePerchlorate is a synthetic oxygen additive in solid fuel propellant for rockets, missiles, and fireworks, and is primarily used by the military and the space industry; it may occur naturally in certain imported agricultural fertilizers.1.33 ppb
7 ppb
Yes
5 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
1,3-Dichloropropene1,3-Dichloropropene is used in chemical synthesis, in agriculture as a soil fumigant and nematocide, and as a corrosion inhibition agent.<0.01 ppb
0.41 ppb
Yes
0.2 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
BromodichloromethaneBromodichloromethane is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.<0.01 ppb
1.55 ppb
Yes
MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb
No
80 ppb
BromoformBromoform is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.<0.01 ppb
0.11 ppb
Yes
MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb
No
80 ppb
DibromochloromethaneDibromochloromethane is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.<0.01 ppb
0.71 ppb
Yes
0.4 ppb
No
80 ppb
Combined Uranium (mg/L)Uranium is a radioactive element commonly found in most rocks; processed uranium ore is used for power generation and weapons manufacture.3.5 ppb
3.5 ppb
Yes
MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb
No
30 ppb
NOTE: Each dot in the above graph represents one month.
* Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

Other Detected Contaminants

ContaminantAverage/
Maximum
Result
Health Limit
Exceeded
Legal Limit
Exceeded

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
NitrateNitrate enters drinking water sources from fertilizer runoff, leaching septic tanks, and erosion of natural deposits; it is also emitted by chemical, petrochemical and metal-finishing industries.3.45 ppm
5.42 ppm
No
10 ppm
No
10 ppm
cis-1,2-Dichloroethylenecis-1,2-Dichloroethylene is a pollutant discharged by various industrial chemical factories from the manufacture of plastic wrap, adhesives and synthetic fiber.0.12 ppb
1.32 ppb
No
70 ppb
No
70 ppb
1,1-Dichloroethane1,1-Dichloroethane is used in industrial chemical synthesis, as a solvent for plastics, paint, varnish, and finish removers and as an insecticide/fumigant.0.14 ppb
1.39 ppb
No
3 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
Combined Uranium (pCi/L)Uranium is a radioactive element commonly found in most rocks; processed ore is used for power generation and weapons manufacture.4.28 pCi/L
11.7 pCi/L
NoNo
15 pCi/L
1,1-DichloroethyleneIndustrial chemical pollutant from manufacture of adhesives, synthetic fibers, refrigerants and plastic wraps.<0.01 ppb
0.17 ppb
No
7 ppb
No
7 ppb
Total trihalomethanes (TTHMs)Total trihalomethanes constitute the sum of four disinfection byproducts: chloroform, bromodichloromethane, dibromochloromethane, and bromoform.0.03 ppb
4.89 ppb
No
9.8 ppb
No
80 ppb
Nitrate & nitriteNitrate and nitrite enter water from fertilizer runoff, leaching from septic tanks, and erosion of natural deposits.2.6 ppm
4.1 ppm
No
10 ppm
No
10 ppm
ChloromethaneChloromethane is a naturally occuring chemical that forms during combustion of plant material; it may be released from the manufacture of silicone, rubber and pesticides, and also forms as a byproduct of water disinfection.<0.01 ppb
0.06 ppb
No
30 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
ChloroformChloroform is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.0.01 ppb
2.68 ppb
No
5.7 ppb
No
80 ppb
VanadiumVanadium is a metal used as an alloying addition to iron & steel; it is discharged from ceramic, glass, textile, photography, metallurgy and rubber industries.9.31 ppb
34 ppb
NoLegal at any levelThis is the Federal Limit. State Limits may be lower.
Chromium (hexavalent)Chromium is a metal that pollutes drinking water due to discharge from steel and pulp mills and erosion of natural deposits.2.66 ppb
4.27 ppb
NoNo
100 ppb
1,4-Dioxane1,4-Dioxane is a stabilizing chemical in industrial solvents and an emerging groundwater pollutant from solvent recycling and plastic manufacturing; it is a probable human carcinogen.0.49 ppb
1.7 ppb
No
3 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
TolueneToluene is a pollutant from petroleum refineries and a chemical used in plastics manufacturing as well as the pharmaceutical, paint and furniture industries.<0.01 ppb
0.05 ppb
No
150 ppb
No
1000 ppb
BromomethaneBromomethane is a pesticide used for soil, grain, indoor air and other applications, and a solvent used to extract vegetable and seed oils.<0.01 ppb
0.04 ppb
No
10 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
Methyl ethyl ketoneMethyl ethyl ketone is a synthetic chemical used as a solvent for paints, coatings, adhesives, printing inks, and other industrial and consumer goods; it occurs naturally in some vegetation and forms during ozonation of drinking water. <0.01 ppb
1 ppb
No
4000 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
Chromium (total)Chromium is a metal that pollutes drinking water due to discharge from steel and pulp mills and erosion of natural deposits.0.24 ppb
4.38 ppb
No
100 ppb
No
100 ppb
ManganeseManganese is a naturally occurring element released from mineral deposits as well as industrial use.1.71 ppb
24 ppb
No
50 ppb
No
50 ppb
CopperCopper is a naturally occuring metal and drinking water contaminant that enters tap water by corrosion of household plumbing systems and erosion of natural deposits.2.12 ppb
27.5 ppb
No
300 ppb
No
1000 ppb
n-Nitroso di-N-Propylaminen-Nitroso di-N-propylamine is a synthetic chemical detected as a contaminant in certain herbicides such as Trifluralin and in extruded rubber products; it is discharged with wastewater from chemical plants.<0.01 ppb
<0.01 ppb
No
<0.01 ppb
Legal at any levelThis is the Federal Limit. State Limits may be lower.
NOTE: Each dot in the above graph represents one month.
* Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

Contaminants Not Detected - 136 chemicals

1,1,1,2-Tetrachloroethane, 1,1,1-Trichloroethane, 1,1,2,2-Tetrachloroethane, 1,1,2-Trichloroethane, 1,1-Dichloropropene, 1,2 Dibromo-3-chloropropane (DBCP), 1,2,3-Trichlorobenzene, 1,2,4-Trichlorobenzene, 1,2,4-Trimethylbenzene, 1,2-Dichloroethane, 1,2-Dichloropropane, 1,3,5-Trimethylbenzene, 1,3-Dichloropropane, 2,2-Dichloropropane, 2,3,7,8-TCDD (Dioxin), 2,4,5-t, 2,4,5-TP (Silvex), 2,4-d, 2-Chloroethylvinyl ether, 3-Hydroxycarbofuran, Acetochlor, Alachlor (Lasso), Aldicarb, Aldicarb sulfone, Aldicarb sulfoxide, Aldrin, Antimony (total), Aroclor 1221, Aroclor 1232, Aroclor 1242, Aroclor 1248, Aroclor 1254, Aroclor 1260, Asbestos, Atrazine, Barium (total), Bentazon (Basagran), Benzene, Benzo[a]pyrene, Beryllium (total), Bromacil, Bromobenzene, Bromochloromethane, Butachlor, Cadmium (total), Caffeine, Carbaryl, Carbofuran, Carbon tetrachloride, Chlordane, Chloroethane, Chlorothalonil (Bravo), cis-1,3-Dichloropropene, Cyanide, Dacthal, Dalapon, Di(2-Ethylhexyl) adipate, Di(2-ethylhexyl) phthalate, Diazinon (Spectracide), Dibromomethane, Dicamba, Dichlorodifluoromethane, Dichloromethane (methylene chloride), Dieldrin, Dimethoate, Dinoseb, Diquat, Endothall, Endrin, Ethyl-t-butyl ether (ETBE), Ethylbenzene, Ethylene dibromide (EDB), Glyphosate, Gross beta particle activity (pCi/L), Heptachlor, Heptachlor epoxide, Hexachlorobenzene (HCB), Hexachlorobutadiene, Hexachlorocyclopentadiene, Isopropyl ether, Isopropylbenzene, Lead (total), Lindane, m- & p- Xylene, m-Dichlorobenzene, m-Xylene, Mercury (total inorganic), Methomyl, Methoxychlor, Methyl isobutyl ketone, Metolachlor, Metribuzin, Molinate (Ordram), Monochlorobenzene (Chlorobenzene), Mtbe, n-Butylbenzene, N-nitrosodi-n-butylamine (ndba), n-Nitrosodimethylamine, N-nitrosomethylethylamine (nmea), N-nitrosopiperidine (npip), N-nitrosopyrrolidine (npyr), n-Propylbenzene, Naphthalene, Nitrite, o-Chlorotoluene, o-Dichlorobenzene, o-Xylene, Oxamyl (Vydate), p-Chlorotoluene, p-Dichlorobenzene, p-Isopropyltoluene, p-Xylene, Pentachlorophenol, Picloram, Prometryn, Propachlor, Radium-226, sec-Butylbenzene, Selenium (total), Silver (total), Simazine, Styrene, Terbacil, Tert-Amyl-Methyl Ether, Tert-Butyl Alcohol, tert-Butylbenzene, Thallium (total), Thiobencarb (Bolero), Total polychlorinated biphenyls (PCBs), Toxaphene, trans-1,2-Dichloroethylene, trans-1,3-Dichloropropene, Trichlorofluoromethane, Trichlorotrifluoroethane, Vinyl chloride, Xylenes (total)

Pollution Summary

33Total Contaminants Detected (2004 - 2009)

Chromium (total), Copper, Manganese, Nitrate & nitrite, Nitrate, Chromium (hexavalent), Vanadium, 1,4-Dioxane, Chloromethane, Bromomethane, Methyl ethyl ketone, n-Nitroso di-N-Propylamine, cis-1,2-Dichloroethylene, Chloroform, Total trihalomethanes (TTHMs), 1,1-Dichloroethylene, 1,1-Dichloroethane, Toluene, Combined Uranium (pCi/L), Aluminum, Arsenic (total), 1,3-Dichloropropene, 1,2,3-Trichloropropane, Bromoform, Bromodichloromethane, Dibromochloromethane, Trichloroethylene, Tetrachloroethylene, Combined Uranium (mg/L), Combined Radium (-226 & -228), Radium-228, Alpha particle activity, Perchlorate

7Agricultural Pollutants
(pesticides, fertilizer, factory farms)

Nitrate & nitrite, Nitrate, Bromomethane, n-Nitroso di-N-Propylamine, Arsenic (total), 1,3-Dichloropropene, Perchlorate

6Sprawl and Urban Pollutants
(road runoff, lawn pesticides, human waste)

Nitrate, Copper, Nitrate & nitrite, Arsenic (total), Tetrachloroethylene, Methyl ethyl ketone

25Industrial Pollutants

Chromium (total), Manganese, Nitrate & nitrite, Nitrate, Chromium (hexavalent), Vanadium, 1,4-Dioxane, Chloromethane, Methyl ethyl ketone, n-Nitroso di-N-Propylamine, cis-1,2-Dichloroethylene, 1,1-Dichloroethylene, 1,1-Dichloroethane, Toluene, Combined Uranium (pCi/L), Aluminum, Arsenic (total), 1,2,3-Trichloropropane, Trichloroethylene, Tetrachloroethylene, Combined Uranium (mg/L), Combined Radium (-226 & -228), Radium-228, Alpha particle activity, Perchlorate

6Water Treatment and Distribution Byproducts
(pipes and fixtures, treatment chemicals and byproducts)

Total trihalomethanes (TTHMs), Chloroform, Bromodichloromethane, Dibromochloromethane, Bromoform, Chloromethane

14Naturally Occurring
(naturally present but increased for lands denuded by sprawl, agriculture, or industrial development)

Nitrate, Copper, Nitrate & nitrite, Arsenic (total), Manganese, Radium-228, Alpha particle activity, Combined Radium (-226 & -228), Combined Uranium (pCi/L), Chromium (total), Combined Uranium (mg/L), Aluminum, Chromium (hexavalent), Chloromethane

10Unregulated Contaminants
EPA has not established a maximum legal limit in tapwater for these contaminants

Vanadium, 1,4-Dioxane, Chloromethane, Bromomethane, Methyl ethyl ketone, n-Nitroso di-N-Propylamine, 1,1-Dichloroethane, 1,3-Dichloropropene, 1,2,3-Trichloropropane, Perchlorate

EPA Violation Summary

Violation CategoryNumber of Violations
Monitoring
(click see violations)
1

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.