A study published in the Interdisciplinary Environmental Review has assessed the presence of microplastics in drinking water sources in Southern India. The work provides new evidence of the spread of plastic pollution and its increasing potential effect on human health.

I. Ronald Win Roy and A. Stanley Raj of Loyola College in Chennai, India, analyzed tap and tank water in Chennai, focusing on areas near the heavily polluted Cooum River and Great Salt Lake. They found microplastic particles in almost every sample tested.

Microplastics are defined as plastic fragments smaller than 5 millimeters. They are usually formed through the breakdown of larger pieces of plastic waste through exposure to sunlight, water, and friction. They have been detected in almost every ecosystem from the remote Arctic ice to the deepest parts of the ocean, which is of obvious broad environmental concern. However, their presence in drinking water is a serious issue with a potentially even more direct effect on public health.

This is the first study of its kind in Southern India, and comes at a time when global plastic production is of even more concern than ever before. In 1970, global production stood at 30 million tons. By 2020, plastic production had reached 380 million tons. Forecasts suggest that figure will have reached 600 million tons annually by 2050.

As plastic use intensifies around the world, waste management systems, particularly in rapidly urbanizing regions, are struggling to keep pace. The result is that plastic debris is increasingly infiltrating both natural and the built environments.

The presence of microplastics in the environment and in drinking water is troubling in itself, but it is their potential to act as vectors for toxic substances that raises even more concern. Fat-soluble compounds can be absorbed on to or even into synthetic polymer particles. Such compounds might include persistent organic pollutants with potentially carcinogenic or endocrine-disrupting effects. Furthermore, microplastics might act as hosts for pathogenic microbes or transport toxic heavy metals.

Once ingested, any toxic payload released in the body might then have detrimental effects on health. Given that tests on blood, placental tissue, and even lung samples have already demonstrated the presence of microplastics in humans, microplastic contamination is becoming a defining feature of the Anthropocene. The development of detection tools, as demonstrated in this study, is urgently needed so that we can more clearly understand the problem and hopefully devise solutions.