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Opinion | Antibiotics are contaminating rivers and posing health risks

Even low concentrations of pharmaceutical effluents pollute our freshwaters and endanger both marine and human life

Biomes, which are distinct communities of flora and fauna that get formed in response to a shared climate, and tissue-specific microbiomes, which are a mix of organisms that coexist in tissues, have an intimate link with each other, jointly impacting human health. While Delhi is struggling with the issue of extremely poor air quality, the problem of poor water quality in rivers plagues the whole country.

Water constitutes 70% of our total body composition. Apart from its use as an essential component for survival, water is required for agricultural and industrial activities, and power generation, thus playing a central role in global food supply, economic prosperity and the survival of all living organisms. Its importance can be gauged by the fact that all major civilizations in ancient times developed along the banks of major rivers.

Our rivers and water bodies are life-supporting assets. But river pollution has become a major cause of concern across the world in the past few decades. Its common causes include industrial discharge, open defecation, untreated waste from chemical and pharmaceutical industries, waste generated by hospitals, clinics and animal husbandry units. Recent reports on the presence of high amounts of myriad pharmaceutical residues in water bodies in Hyderabad only highlight the sordid state of affairs with the country’s handling of urban and industrial waste, and the consequent pollution of water bodies. Indeed, several rivers in the world, including those in India, have been reported to have high concentrations of antibiotics such as ciprofloxacin, norfloxacin, oxytetracycline and ofloxacin.

What is the threat posed by a high concentration of chemicals, particularly drugs, in surface and ground water?

The English physician John Snow was the first to correctly suggest that the cause of London’s “Broad Street cholera outbreak" in 1854 was the leakage of sewage full of faecal bacteria into a public well. But it is not just the consumption of contaminated water that is a health hazard. In 2000, Cifuentes et al identified irrigation as a link between water pollution and health, while Carr in 2001 highlighted bathing, food and person-to-person contact as modes of disease transmission from polluted water. In 2010, Ebenstein reported that a one-grade deterioration in Chinese river water quality was associated with a 9.7% increase in digestive cancer incidence. In 2011, Brainerd and Menon reported that pregnant women being exposed to a 10% increase in agrichemical levels in Indian rivers during their first month of conception was associated with an 11% increase in the likelihood of one-year mortality among newborns.

Infants are also highly susceptible to water-borne pathogens (Fewtrell and Bartram, 2001) and infant mortality serves as a good yardstick, especially in India, where infant mortality rates remain higher than the global average. The additional advantage of using this indicator is that it limits concerns of prior exposure to pollution. By correlating upstream and downstream water quality across time and space, we find that the average effect of a 1% increase in faecal coliforms is an additional 3-5 deaths per 100,000 births in a given month. In comparison, the corresponding downstream infant mortality impact is about 1-2 deaths per 100,000 births.

Unfortunately, it has been observed that Indian industries often discharge untreated or partially treated water into nearby water bodies or rivers, leading to severe water pollution and water toxicity. Continuous discharge of untreated fluids into rivers gradually pollutes its water and makes it useless for drinking, agriculture and further industrial use. In 1985, the Indian government launched the Ganga Action Plan (GAP) to clean up the Ganga river, India’s longest. In the ensuing three decades, GAP was extended first to other rivers in the Ganga basin, and later to rivers all over India. Currently, 190 towns in 20 states along 41 rivers are regulated under what is now known as the National River Conservation Plan (NRCP), India’s flagship water pollution clean-up policy. Brandon and Homman (1995) estimate the impact of domestic water pollution on a broader swathe of illnesses. They find that providing clean water supply and sanitation to the whole of India would save $3-8 billion by way of forgone earnings. In particular, they suggest that 59% of annual environmental costs in India are incurred by surface water pollution.

As pharmaceuticals are designed to interact with living organisms at low doses, even low concentrations affect freshwater ecosystems. A recent OECD report cited in The Times Of India estimates that 10% of pharmaceuticals have the potential to cause environmental harm—hormones, painkillers and antidepressants are the biggest concerns. There is growing evidence of negative impact, with laboratory and field tests showing traces of oral contraceptives causing feminization in fish and amphibians, and residues of psychiatric drugs altering fish behaviour. Unless adequate measures are taken to manage risks, the situation is set to worsen, as the use of pharmaceuticals rises with ageing populations, advances in healthcare, rising meat and fish production, and the increased use of antibiotics for livestock.

India wants to clean its rivers by 2030, but it may remain a distant dream if the authorities continue with business as usual. The target seems difficult, as the government’s own data reveals that the number of polluted stretches of rivers across the country has increased in the past few years, and the ambitious plan to clean the Ganga is yet to yield tangible results.

Suman Kapur is senior professor, BITS Pilani, Hyderabad

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