The Environmental Effects Of (Excreted) Pharmaceuticals
Concerns about the possible effects of pharmaceuticals, their metabolites and other chemicals, including household products is developing into a high profile issue in Europe, the United States, Canada and other countries around the world. The presence of these compounds and the inconsistencies in the way they are disposed has made their presence in the environment inevitable. After release into the environment, most pharmaceutically active compounds (PhACs) also known as active pharmaceutical ingredients (APIs) are eventually transported to the aqueous domain and are expected to be only partially degraded and transformed into other products by photo-transformative, physicochemical and biological degradation reactions. However evidence available now suggests otherwise. Every year tonnes of these harmful chemicals are emptied into rivers and other surface waters in the effluent from sewage treatment plants since these plants generally are not able to remove all trace constituents. Their sources in natural waters are not limited to excretion of parent compounds and their metabolites by individuals and pets but also include disposal of unused medications to sewage systems, underground leakage from sewage system infrastructures, release of treated or untreated hospital wastes, disposal by pharmacies and physicians, and humanitarian drug surplus to domestic sewage systems.
A recent study of three plant sites in India (Ankleshwar, Nandesari & Vapi) by Greenpeace revealed that about 250-270 million liters of liquid and 100 million pounds of solid waste is produced per day and per year respectively. About 19% of which is from drugs and 5% from organic chemicals and 8% from pesticides. Most of this is dumped into ground water and local water ways surrounding the plants. Thus these water bodies now contain poisonous chemicals such as benzene, 1,3- and 1,4-dichlorobenzenes. Dichlorobenzene for instance is a persistent chemical substance resistant to microbial degradation.
The presence of excreted pharmaceuticals and chemicals even at low levels presents analytical challenges and the environmental impact and public health effects of long-term, low-level exposure and combinatory effects are potential detrimental to human health, the environment and the flora and fauna. Consequently, it is prudent to consider the options available to prevent excreted pharmaceuticals and chemicals from getting into the environment and reaching drinking water, surface waters such as rivers and lakes, ground waters, and sediments. This will aid in forecasting their potential long-term (chronic) effects on man, aquatic life and the environment. The issue has become more pronounced due to increasing concern as population density and consumption of pharmaceuticals.
More worrying is the fact that pharmaceuticals in the environment have become more persistent and even for compounds are short life times, the effects of long-term exposure and combinatory effects need to be addressed. Available literature suggests the quantity of pharmaceuticals already excreted into the environment is enormous; and will continue to increase as long as population and pollution increase leading to a disruption of the delicate balance of the ecosystem and environmental biomes, niches, food chains, and the biodiversity of organisms therein. The presence of pharmaceuticals such as antibiotics in the aquatic environment poses a potential threat to ecosystem function and human health. Scientific findings from research carried out at Trent University Canada revealed that after a 100 day exposure of Japanese Medakas fish to the effluent water samples with concentrations of 0.1 ppt estrone (a type of estrogen) and other chemicals, the fish began to exhibit intersexual changes (showing both male and female characteristics). At 1000 ppt all the males transformed to females. Another study by researchers in London found that exposure an even ppt of estrogen will trigger the production of Vitellogen, a female protein responsible for making yolk in eggs, in male fish. American researchers in a separate report found that the exposure of excreted pharmaceuticals has resulted in the sterility of male walleys, birth defects in alligators and also other water dwelling birds and species of wildlife. In humans the effects of excreted pharmaceuticals can be attributed to cancers, hormonal imbalance, immune disabilities, birth defects, cancer (carcinogenic), fetal deaths, decreased fertility, male and female reproductive dysfunction and is known to interfere with hormonal and endocrine systems such as those responsible for insulin and thyroid hormones.
Some pundits may argue about whether or not there are adverse human health effects from cumulative lifetime exposures to the low concentrations and complex mixtures of pharmaceuticals. However, we must not risk their effects, however mild, on sensitive sub-populations such as children, women of child-bearing years, the elderly, and people with suppressed immune systems; by making rhetoric out of the problem like humanity has other issues like global warming in the past.
In other to arrest these negative trends and forestall future eventualities, the following measures can be employed to address the situation. Because numerous studies reveal that majority of pharmaceuticals in the environment come from patient use, individuals must be cautioned on the effects of such actions on the future of coming generations and the long term diversity protection of the environment. The government and NGOs must make concerted efforts to educate people on the dangers of dumping pharmaceuticals into the environment and encourage them to report if noticeable any change in water or environment that can be attributed to the presence of pharmaceuticals in the environment. The academia should be stimulated by the government and proper environmental legislation put in place to spur research and garner rigorous efforts towards investigating the short and long term effects of pharmaceuticals excreted into the environment. Enacted legislation should be enforced more strongly to arrest the unwanted and wanton disposal of pharmaceuticals, chemicals, agricultural chemicals and pesticides into the streams, rivers and water bodies by individuals and industry. A database-cum-databank of research into pharmaceuticals excreted into the environment should be created to enhance the knowledge base of the situation, its effects and proffer solutions based on the twelve (12) principles of Green Chemistry which include; Prevent Wastes, Renewable materials, Omit derivatization steps, Degradable chemical products, Use safe synthetic methods, Catalytic reagents, Temperature, pressure ambient, In-process monitoring, Very few auxiliary substances, E-factor, maximize feed in product, Low toxicity of chemical products, Yes, it is safe. Approval and incentives should be granted to firms and companies who employ green technologies and techniques in pharmaceutical waste disposal. Finally policy and technological framework structures must be created to identify more potent pharmaceuticals as the target of future research on possible effects of pharmaceuticals in the environment.
This way mankind can take a huge step in the quest to be more sustainable-responsible for her action towards the environment and future generations.