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International Comparison of Water Quality

International Comparison of Water Quality

Comparison of TWD's Tap Water Quality with U.S., Japan, E.U., W.H.O.'s Guidelines, and Water Quality Standards of EPA, R.O.C.

       

Microbial Parameters

Parameters

TWD's
Tap Water
Quality

Maximum Contaminant Level

Taiwan
(2017)

U.S.
(2012)

Japan
(2015)

E.U.
(2015)

W.H.O.
(2011)

1.Total Coliforms
(CFU/100ml,MPN/100ml)

<1

6

5.0%
*1*2

0

0

0

2.Total Bacterial
Count (CFU/ml)

<1

100

-

100

*5
(22˚C)

0

Unit : mg/L (unless specified otherwise)
Maximum Contaminant Level Goal(MCLG):The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety and are non-enforceable public health goals
*1. No more than 5.0% samples total coliform-positive in a month. (For water systems that collect fewer than 40    routine samples per month, no more than one sample can be total coliform-positive per month.)
*2. Fecal coliform and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animals wastes.

Comparison of TWD Tap Water Quality with U.S., Japan, E.U., W.H.O. Guidelines, and Water Quality Standards of EPA, R.O.C.

   

Physical Parameters

Parameters

TWD
Tap Water
Quality

Maximum Contaminant Level

Taiwan
(2017)

U.S.
(2012)

Japan
(2015)

E.U.
(2015)

W.H.O.
(2011)

1.Odor (TON)

1

3

3*3

*5

*5

*5

2.Turbidity (NTU)

0.18

2

TT*4

2

*5

1.5

3.Color (Pt-Co units)

2

5

15*3

5

*5

5

Unit : mg/L (unless specified otherwise)
NTU = nephelometric turbidity unit.
*3. National Secondary Drinking Water Regulations (NSDWRs or secondary standards)
*4. TT :Treatment technique required
*5. Acceptable  to consumers and no abnormal change

Comparison of TWD Tap Water Quality with U.S., Japan, E.U., W.H.O. Guidelines, and Water Quality Standards of EPA, R.O.C.

Chemical Parameters

Parameters

TWD
Tap Water
Quality

Maximum Contaminant Level

Taiwan
(2017)

U.S.
(2012)

Japan
(2015)

E.U.
(2015)

W.H.O.
(2011)

(A) Substances affecting health

1. Arsenic (As)

ND
(< 0.00079)

0.01

0.01

0.01

0.01

0.01

2. Lead (Pb)

ND
(< 0.00064)

0.01

0.015*6

0.01

0.01

0.01

3. Selenium (Se)

ND
(< 0.00154)

0.01

0.05

0.01

0.01

0.01

4. Chromium (Cr)

ND
(< 0.00022)

0.05

0.1

0.05
(Cr6+)

0.05

0.05

5. Cadmium (Cd)

ND
(<0.00042)

0.005

0.005

0.003

0.005

0.003

6. Barium (Ba)

0.006
(<0.00045)

2.0

2.0

-

-

0.7

7. Antimony (Sb)

ND
(<0.00073)

0.01

0.006

-

0.005

0.02

8. Nickle (Ni)

ND
(< 0.00023)

0.1

-

-

0.02

0.07

9. Mercury (Hg)

ND
(< 0.00008)

0.002

0.002

0.0005

0.001

0.006

10.Cyanide (CN-)

ND
(< 0.003)

0.05

0.2

0.01

0.05

-

11.NO- 2-N
(Nitrite Nitrogen, as N)

ND
(< 0.0005)

0.1

1

0.04

0.1

3

Disinfection by-product

12.Trihalomethanes (THMs)

0.0051

0.08

0.08

0.1

0.1

*7

13. Haloacetic acids
(sum of concentrations of Monochloroacetic acid(MCAA), Dichloroacetic acid, Trichloroacetic acid(DCAA), Monobromoacetic acid(MBAA) & Dibromoacetic acid(DBAA))

0.00603

0.060

0.06

0.02 (MCAA)
0.03 (DCAA)
0.03
(TCAA)

-

0.02 (MCAA)
0.02
(TCAA)

14. Bromate

ND
(<0.00045)

0.01

0.01

0.01

0.01

0.01

15. Chlorite

ND
(<0.00082)

0.7

1

-

-

0.7

Volatile Organics

16.Trichloroethylene

ND
(<0.000028)

0.005

0.005

0.01

*8

0.02

17.Carbon Tetrachloride

ND
(<0.000031)

0.005

0.005

0.002

-

0.004

18.1,1,1-Trichloroethane

ND
(<0.000023)

0.20

0.20

0.06

-

-

19.1,2-Dichloroethane

ND
(<0.000036)

0.005

0.005

-

0.003

0.03

20.Vinyl chloride

ND
(<0.00033)

0.002

0.002

-

0.0005

0.0003

21.Benzene

ND
(<0.0003)

0.005

0.005

0.01

0.001

0.01

22.Para-Dichlorlbenzene

ND
(<0.000028)

0.075

0.075

-

-

0.3

23.1,1-Dichloroethylene

ND
(<0.000028)

0.007

0.007

0.04

-

-

24. Dichloromethane

ND
(<0.00062)

0.02

0.005

0.02

-

0.02

25. 1,2-Dichlorobenzene

ND
(<0.00035)

0.6

0.6

-

-

1

26. Toluene

ND
(<0.00036)

0.7

1

-

-

0.7

27. Xylenes

ND
(<0.000072)

0.5

10

-

-

0.5

28.
cis-1,2-Dichloroethene

ND
(<0.00003)

0.07

0.07

-

-

-

29. trans-1,2-Dichloroethene

ND
(<0.000023)

0.1

0.1

-

-

-

30. Tetrachloroethene

ND
(<0.000032)

0.005

0.005

0.01

*8

0.04

Pesiticides

31.Endosulfan

ND
(<0.000003)

0.003

-

-

*10

-

32.Lindane

ND
(<0.0000019)

0.0002

0.0002

-

*10

0.002

33.Butachlor

ND
(<0.00024)

0.02

-

-

*10

-

34.2.4-Dichlorooxyacetic acid

ND
(<0.00017)

0.07

0.07

-

*10

0.03

35.Paraquat*9

ND
(<0.0044)

0.01

-

-

*10

-

36.Methomyl

ND
(<0.00239)

0.01

-

-

*10

-

37.Carbofuran

ND
(<0.00236)

0.02

0.04

-

*10

0.007

38.Isoprocarb

ND
(<0.00249)

0.02

-

-

*10

-

39.Methamidophos

ND
(<0.00255)

0.02

-

-

*10

-

40.Diazinon

ND
(<0.00000144)

0.005

-

-

*10

-

41.Parathion

ND
(<0.0000026)

0.02

-

-

*10

-

42.EPN

ND
(<0.0000119)

0.005

-

-

*10

-

43.Monocrotoohos

ND
(<0.0000478)

0.003

-

-

*10

-

Persistent organic pollutants, POPs

44. Dioxin
(pg WHO-TEQ/L)

0.002

3

3

-

-

-

(B) Substances probably affecting health

1.Fluoride (F-)

0.04

0.8

4.0*11

0.8

1.5

1.5

2.NO3-N
(Nitrate Nitrogen ,As N)

0.67

10.0

10.0

45

50

50

3.Silver (Ag)

ND
(<0.00041)

0.05

0.1*3

-

-

-

(C)Substances affecting palatability

1.Iron (Fe)

0.001

0.3

0.3*3

0.3

0.2

0.1

2.Manganese (Mn)

0.002

0.05

0.05*3

0.05

0.05

0.05

3.Copper (Cu)

ND
(<0.00056)

1.0

1.0*3
1.3*6

1.0

2.0

2.0

4.Zinc (Zn)

0.002

5.0

5.0*3

1.0

-

-

5.Sulfate (SO4-2)

10.1

250

250*3

-

250

-

6.Phenols

ND
(<0.0009)

0.001

-

0.005

-

-

7.MBAS
(Anionic Surfactant, Methylene Blue Activated Substance)

ND
(<0.03)

0.5

-

0.2

-

-

8.Chloride (Cl-)

7.8

250

250*3

200

250

-

9.NH3-N (Ammonia Nitrogen, As N)

ND
(<0.011)

0.1

-

-

0.5

-

10.Total Hardness*12, as CaCO3

37.5

300

-

-

-

-

11.Total Dissolved Solids

65

500

500*3

500

-

-

12. Aluminium
(Total Al)

0.051

0.3

0.05~0.2*3

0.2

0.2

0.1

D. Residual chlorine

0.58

0.2~1.0

4

-

-

0.5-1.5

E. pH value

7.2

6.0~8.5

6.5~8.5*2

5.8~8.6

6.5~9.5

8.2~8.8
(25˚C)

ND : Non detected.
Unit : mg/l (unless specified otherwise)
*6. Lead and copper are regulated by a Treatment Technique that requires systems to control the corrosiveness of their water. If more than 10% of tap water samples exceed the action level, water systems must take additional steps. For copper, the action level is 1.3 mg/L, and for lead is 0.015 mg/L.
*7. The sum of the ratio of the concentration of each to its respective quideline value should not exceed 1.
*8. Sum of concentrations of Tetrachloroehtene and Trichloroethene should not exceed 0.01 mg/L.
*9.  paraquat (as dichloride), quivalent to 0.007 mg/L for paraquat ion.
*10 . Pesticides,each 0.0001 mg/L ,Total: 0.0005 mg/L.
*11. USEPA also set the SMCL(Secondary Maximum Contaminant Limits)as 2 mg /L for fluoride Public acceptance of hardness varies considerably.
*12. Generally, hardness levels between 80 and 100 mg/L (as CaCO 3 ) are considered acceptable; levels greater than 200 mg/L are considered poor but can be tolerated; those in excess of 500 mg/L are normally considered unacceptable.

  • Hit: 38221
  • Updated: 2017/8/7 11:12
  • Reviewed: 2017/10/3 14:35

  • Source: Taipei Water Department