It is a widely accepted norm that rainwater is a safe source of drinking water, as it supplies many of our water bodies. But the latest studies demonstrate novel insights into persistent chemical pollution and rainwater contamination. Researchers claim rainwater is not right for consumption due to alarming levels of toxic compounds like PFAS (Poly-FluroAlkyl Substances). Other major pollutants include acidic pollutants, characterized by hazardous oxides of sulphur and nitrogen due to industrial emissions. These harmful oxides combine with water and oxygen in the atmosphere to cause acid rain with low pH levels, which makes it unsafe for drinking purposes. . Furthermore, it was substantiated by the latest US guidelines for PFOA (Perfluorooctanoic Acid) in drinking water which examined rainwater from diverse parts of the world and was judged as unsafe to drink.
PFAS or the ‘forever chemicals’
PFAS or The per- and Poly-FluroAlkyl Substances are a huge class of industrial chemicals which have been widely used in manufacturing of various products and equipments since the time of industrial boom. There are numerous sorts of PFAS, for instance, Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS)that constitute some of the extensively employed chemicals in the PFAS group. They are commonly referred to as the ‘forever chemicals’ because of its lack of disintegration due to strong carbon- fluorine bonds with the elements. Henceforth, they don’t break down over time and are persistent, and get easily transported via air and water, causing major environmental concerns and health issues. PFAS are pervasive and can be traced everywhere like our water, soil, air, and food as well as in materials found in our homes or workplace.
According to the health advisories for four PFAS publicised by the US Environmental Protection Agency (EPA) in June 2022, the updated non-regulatory lifetime drinking water health advisories for PFOA and PFOS were 4 pg/L and 20 pg/L, respectively. There has been a shocking decline in PFAS drinking water guidelines over the last 22 years. For instance, if we are taking the case of the US, the PFOA drinking water guidelines for West Virginia was 150000 ng/L, which exceeds the US EPA drinking water lifetime advisory for PFOA of 4pg/L, by a factor of 37.5 million. The risk assessment study about the population exposed to the PFAS revealed that the constant contact with these chemicals develop a variety of health risks. The most common non-cancer effect included the suppression of vaccine response, which can have an adverse effect in the recent scenario of the pandemic.
Health risks:
The latest studies have shown that exposure to certain levels of PFAS may lead to adverse effects like poor reproductive health , fertility problems or recurrent high blood pressure in pregnant women. These oncogenic substances also lead to amplified threats of some cancers, such as prostate, kidney, and testicular cancers. It further leads to a poor immunity system, reduced vaccine response and frequent risks of infection. It hinders development and growth in children leading to an array of issues like behavioural anomalies, accelerated puberty, delayed growth rate and low birth weight etc. It also causes detrimental effects on hormones, causing hormone imbalance and disorders, increased cholesterol levels and magnified chances of obesity.
The Acid Rain Program
According to the Acid Rain Program run by the US Environmental Protection Agency, the drastic effects of Acid rain can be countered through regulations like Clean Air Markets, Clean Air Act, Clean Air Status and Trends Network (CASTNET), National Atmospheric Deposition Program (NADP) and Long-term Monitoring (LTM) Network. The acid rain program aimed at a two million ton drop in the emissions of nitrogen and sulphur oxides below the levels of the 1980 by the year 2000. These cutbacks have been attained through the incorporation of coal-fired utility boilers, equipped with low-NOx burner technologies. The program was executed in two phases, the Phase I ran from 1996 to 1999 and concentrated on Group 1 boilers, whereas the Phase II began in 2000 and focused on Group 1 and Group 2 boilers.
Solutions:
Although the levels of PFAS are universally present all across the globe, the levels are relatively low in the thinly populated areas like Antarctica and the Tibetan Plateau. The global restrictions and regulatory acts on PFAS and regulations on industries producing these toxic substances can help in decreasing the more harmful and long-term impacts. The Global leaders and environmental agencies must spread awareness about the rising levels of hazardous chemicals in the atmosphere which further paves its way to the food chain and leads to health threats. The usage of PFAS must be firmly restricted in all possible ways through treaties, taxes and legal contracts, reducing the production, emissions and persistence of these chemicals.
To reiterate the depth of rainwater toxicity, it must be noted that many tropical and arid countries employ rainwater harvesting systems and depend on rainwater as a major source of drinking water. One of the practical solutions to rainwater toxicity is the incorporation of a well planned treatment plant to get rid of the hazardous chemicals. For instance, the use of a filtration tank with a combination of gravel, mollusk sand and activated carbon, further followed by UV rays treatment that will aid in reducing the pollutant levels in rainwater. The Global organizations must collaborate in spreading awareness about the chemical toxicity to the public and propose possible preventive measures like delivering safe drinking water and avoiding the exposure to contaminated water. Moreover, environmental agencies must invest in research programmes focusing on the mitigation of the ever-increasing chemical pollutants and its harmful outcomes.The increasing level of toxicity must be viewed as an issue of environmental justice violation which must be voiced out at a global and grassroot level.