A growing number of babies across the world are being born with small penises and malformed genitals due to pollution, according to a new book written by environmental scientist and reproductive epidemiologist Dr Shanna Swan.

As per media reports, the book titled ‘Count Down’ gives insight into how pollution is threatening the sperm count, modifying male and female reproductive development and pushing the human race to an “existential crisis” in fertility rates.

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According to Swan, a chemical named phthalates, which is used in industries to manufacture plastics, is affecting the human endocrine system. This system is where hormones are produced, stored, and released.

Swan first examined what is called phthalate syndrome, which is usually observed in rats. In her research, she found that exposure to this chemical means a human is most likely to be born with shrunken genitals.

Phthalate is being transmitted into toys and foods, Swan says. She further adds that the chemical can mimic the hormone oestrogen, disrupting the natural production of the hormone. This can be linked to improper sexual development in infants and behaviours in adults.

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As per a 2017 study, sperm levels among men in Western countries had dropped by more than 50% over the past four decades. This outcome was released after examining 185 studies involving nearly 45,000 healthy men, as per the media reports.

Swan is a professor in environmental medicine and public health at the Mount Sinai Hospital in New York City. She has based her book on peer-reviewed studies. According to her, most men would be unable to produce sperm by 2045 due to the rapid decrease in the fertility rate.