Over the years, studies have been conducted to establish the effects of estrogen found in drinking water on human as well as aquatic health. Research has established that estrogen from oral contraceptives, especially Ethynyl-Estradiol or EE2 and excreted naturally occurring E2 finds its way into rivers and streams. However, the potential of the levels of the estrogen in drinking water to cause adverse effects to human beings is debatable. This paper explores the topic of estrogen in drinking water and its effects on onset of puberty.
Levels of Estrogen in Drinking Water
Various studies have concluded that the levels of estrogen in drinking water are negligible and not likely to have significance in human health (Christensen, 1998). Compared to endogenously produced estrogen, risk of health effects from environmental sources of estrogen was found to be negligible (Laurenson et al., 2014). According to Webb et al. (2003), indirect exposure to synthetic estrogen EE2 in worst-case scenarios was 3 to 4 times lower, in orders of magnitude, than endogenously produced E2. In addition, dietary exposure to estrogen such as from dairy products is higher than environmental exposure especially from drinking water. Dietary exposure was found to be the primary pathway for exposure to estrogen except for women who take estrogen as a contraceptive (Caldwell et al., 2010).
Furthermore, the predicted environmental concentrations (PECs) in drinking water are a bit lower than in surface water since intakes of drinking water are on <10% of river or stream segments. Moreover, these segments are not likely to be immediately downstream of publicly owned treatment works (POTWs). It is the steam segments that are immediately downstream of POTWs that contain the highest PECs of Estrogen for surface waters (Webb et al., 2003). According to Laurenson et al. (2014), mean-flow long-term PECs for EE2 for about 99% of surface water in downstream segments of POWTs were lower than the predicted no-effect concentration (PNEC). These levels are exceeded only in localized segments dominated by effluents. Effects of Estrogen in Drinking Water on Human Health Due to the low levels of estrogen especially the synthetic EE2 in drinking water, its effect on human health particularly onset of puberty is not significant. Caldwell et al. (2010) found that the estrogens that are potentially present in water, both prescribed and total were not causing adverse effects to residents in U.S. This was inclusive of sensitive populations such as pre-pubertal males. The results indicate that the amounts of estrogen present in drinking water are not significant enough to alter the sexual development of individuals that would lead to early onset of puberty. Caldwell et al. (2010) compared exposures in drinking water to set toxicity benchmarks such as WHO Acceptable Daily Intakes (ADI), and the Threshold for Toxicologic Concern (TTC). Other benchmarks were occupational exposure limits and the Australian Guidelines for Water Recycling. Results showed that pre-pubertal children had higher exposure to estrogen from dietary intake than from drinking water (Caldwell et al., 2010). The traces of estrogen in drinking water were far much lower than estrogen consumed in milk and other products. Moreover, after considering all estrogen sources in drinking water, a child's exposure is 150-folds lower in drinking water than in milk only. Conclusion Studies show that exposure to estrogen in drinking water does not cause adverse effects to human beings. The levels of estrogen in drinking water are negligible and are lower than the predicted no-effect concentrations (PNECs). Furthermore, studies show that dietary intake of estrogen from such products as milk and other products, is significantly higher than intake from drinking water. Drinking water contains less levels of estrogen than surface water particularly because it is drawn from <10% of stream segments which are far downstream from POTWs.
- Caldwell, D.J., Mastrocco, N.E., Johnston, J., Yekel, H., Pfeiffer, D., Hoyt, M’& Anderson, P.D. (2010). An assessment of potential exposure and risk from estrogens in drinking water. Environmental Health Perspective, 118(3), 338-44.
- Christensen, FM. (1998). Pharmaceuticals in the environment’a human risk? Regulatory Toxicology and Pharmacology, 28(3), 212’221.
- Laurenson, P.J., Bloom, R.A., Page, S., & Sadrieh, N. (2014). Ethinyl estradiol and other human pharmaceutical estrogens in the aquatic environment: a review of recent risk assessment data. The AAPS Journal, 16(2), 299-310.
- Webb, S., Ternes, T., Gibert, M., & Olejniczak, K. (2003). Indirect human exposure to pharmaceuticals via drinking water. Toxicology Letters, 142(3), 157’167.
