Know Your Environment. Protect Your Health.

Simazine

Horsepen Bayou Municipal Utility District

Simazine is a hormone-disrupting herbicide related to atrazine. It affects the male and female reproductive systems. In studies of laboratory animals, simazine increases blood levels of estrogen, decreases prolactin and progesterone, and causes mammary and ovarian tumors.

 

12

Samples

0

Samples exceeding legal limit (MCL)

2

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND20ND
20190.0400 ppb21ND - 0.0800 ppb
20200.1000 ppb220.1000 ppb
20210.0800 ppb220.0700 ppb - 0.0900 ppb
20220.0450 ppb21ND - 0.0900 ppb
20230.205 ppb220.200 ppb - 0.210 ppb

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.1 ppb

The EWG Health Guideline of 0.1 ppb for simazine was defined by EWG based on epidemiological studies of human exposure to atrazine in drinking water. This health guideline protects against harm to the developing fetus, harm to the reproductive system and hormone disruption.

EPA Maximum Contaminant
Level (MCL): 4 ppb

The legal limit for simazine, established in 1992, was based on toxicity studies in laboratory animals conducted in the 1980s. This limit does not fully protect against harm to the reproductive system, harm to the developing fetus, and hormone disruption.

ppb = parts per billion

All test results

Date Lab ID Result
2018-03-28AE20494ND
2018-03-28AE20495ND
2019-02-20AE55151ND
2019-02-20AE551520.0800 ppb
2020-02-03AE966840.1000 ppb
2020-04-27AF083000.1000 ppb
2021-03-23AF479080.0900 ppb
2021-06-09AF572730.0700 ppb
2022-05-03AF95396ND
2022-05-03AF953980.0900 ppb
2023-05-10AG401040.210 ppb
2023-05-10AG401050.200 ppb