Contraceptives like birth control pills contain synthetic estrogen and progestin hormones that regulate fertility when taken regularly. However, improving wastewater treatment alone may not suffice to eliminate these trace chemicals that eventually enter sources of drinking water. Advanced chromatographic techniques could potentially enable the quantification and removal of contraceptive hormones to ensure water safety.
Modern birth control formulations provide measured doses of ethinylestradiol (EE2) or mestranol as estrogen components along with progestins like levonorgestrel. Unfortunately, the potent activity of these hormones allows them to exert physiological effects even at low concentrations typically observed in municipal water supplies. This has raised concerns regarding potential health impacts on wildlife and humans.
Why Are Contraceptive Hormones Present in Drinking Water?
After oral ingestion, the human body absorbs and utilizes only a fraction of contraceptive hormones while excreting the rest via urine and feces. Conventional wastewater treatment methods involving sedimentation tanks, microbial decomposition, and chlorine disinfection cannot eliminate these biologically active compounds.
Several studies have detected estrogenic hormones like EE2 and estrone in effluents at nanogram per liter levels.1 Additional contamination may occur due to improper disposal of expired pills into landfills and sewers. Unabsorbed hormones in feces may further leach into groundwater or surface water bodies. As a result, trace quantities of contraceptive estrogen and progestins persist through multiple stages of the water treatment process and end up in tap water.
Adverse Effects of Contraceptive Hormones in Drinking Water
The presence of contraceptive hormones like EE2 in drinking water, even at parts per trillion concentrations, raises concerns about potential long-term health consequences in humans. Fetal development in pregnant women may be affected. These xenoestrogens can also interfere with the endocrine system and lead to issues like early puberty in children.
Wildlife living in surface water contaminated by treatment plant effluents display reproductive abnormalities. Male fish have shown signs of feminization, reduced sperm production, and egg yolk protein accumulation.2 Aquatic invertebrates and amphibians are also vulnerable. Endocrine disruption can alter metabolism and immunity as well.
How Can Chromatography Help Detect and Analyze Hormones in Water?
Advanced chromatographic systems can isolate, identify, and quantify contraceptive hormones in water with high accuracy and sensitivity.
High-Performance Liquid Chromatography (HPLC)
HPLC utilizes a column packed with fine particles and a precise pump to pass pressurized solvents along with the water sample. Target compounds get separated based on differential interactions with the stationary phase. The eluting hormones are then analyzed using a suitable detector.
- A UV-Vis detector can measure hormones like EE2 having chromophores. Fluorescence detection offers even better sensitivity.
- Mass spectrometry (LC-MS) enables definitive identification and quantification of hormones in water based on molecular mass.
Sample pre-treatment steps like solid-phase extraction can extract and concentrate hormones from large sample volumes before HPLC analysis. This enhances detection limits.
Gas Chromatography (GC)
GC instruments vaporize and inject sample components into a heated column using an inert carrier gas. Separation occurs based on partitioning between the gaseous mobile phase and a liquid stationary phase coated on the column interior.
- GC-MS allows the characterization of thermally stable hormones like progesterone in water supplies.
- Derivatization can improve volatility and achieve detection limits down to the nanogram per liter range.
A Comparative Table Showing the Relation Between HPLC and GC for Hormone Analysis
| Parameter | HPLC | GC |
|---|---|---|
| Sample preparation | Often needs extraction only | Derivatization frequently required |
| Nature of mobile phase | Liquid | Gas |
| Column temperature | Ambient to 80°C usually | Up to 300°C |
| Suitable hormones | Polar hormones like estrogens | Non-polar hormones like progesterone |
Thus, GC and HPLC offer complementary options for separating and detecting contraceptive hormones in environmental water samples.
How Can We Eliminate These Hormones From Drinking Water?
Along with quantification using chromatography, additional treatment solutions could help minimize discharge and remove persistent hormones:
- Upgrading wastewater plants with activated carbon or ozone treatment to degrade hormones like EE2.
- Introducing biofilters with microbes that can metabolize hormones and render them inactive.
- Employing reverse osmosis and UV oxidation during drinking water purification.
- Discouraging disposal of medications into sewers and trash. Proper collection systems must be established.
Proper Disposal of Unused Contraceptive Pills
To prevent contamination of water sources, leftover or expired birth control pills should never be flushed or poured down the drain. The FDA recommends mixing them with dirt, cat litter, or coffee grounds before putting them in the trash. This renders the hormones inactive and unusable.
Some municipalities have household pharmaceutical take-back programs that allow for safe disposal at authorized collection centers. Returning expired contraceptives to the pharmacy for proper disposal is also an environmentally responsible option. These measures help keep potent steroids out of sewage systems and the aquatic ecosystem.
Conclusion
Leftover contraceptive hormones entering water resources via human excretion and improper disposal lead to a potential public health issue. Advanced chromatographic techniques now enable the detection of these endocrine disruptors in environmental samples at trace levels. Combining quantification data with specialized treatment solutions could help restrict hormone contamination of drinking water. Implementing responsible disposal practices is also essential to avoid such micropollutants at the source itself.
Frequently Asked Questions
Why are contraceptive hormones still present in tap water after wastewater treatment?
Conventional processes like chlorination and microbial biodegradation cannot completely degrade persistent synthetic hormones like EE2 at the trace concentrations typically observed. They pass through multiple treatment stages and end up in drinking water.
What concentrations of hormones like estrogens are found in drinking water?
Treated wastewater effluents and surface water bodies receiving them show estrogenic hormones like estrone and EE2 at low parts per trillion levels. Tap water concentrations are typically under 10 ng/L.
How can hormones in parts per trillion concentrations produce physiological effects?
Synthetic contraceptive hormones have very high potency due to optimized structural stability. Even low nanogram per liter levels can activate hormone receptors and disturb endocrine pathways.
Are hormonal contraceptives the only source of water contamination?
Livestock manure, plasticizers, and pharmaceuticals also contribute estrogen compounds. However, the high activity and abundance of contraceptive hormones make them a major concern.
Can activated carbon filtration remove hormones from drinking water?
Yes, advanced treatments like granular activated carbon adsorption and ozone oxidation at water treatment plants can help eliminate hormones like estradiol and progesterone.