Impact of air pollution and heavy metal exposure on sperm quality: A clinical prospective research study

Abstract

Exposure to air pollution poses significant risks to human health, including detrimental effects on the reproductive system, affecting both men and women. Our prospective clinical study aimed to assess the impact of prolonged air pollution exposure on sperm quality in male patients attending a fertility clinic. The current study was conducted at Sri Narayani Hospital and Research Centre in Vellore, Tamil Nadu, India, and the study examined sperm samples obtained from individuals with extended exposure to air pollution. Microscopic analysis, including scanning electron microscopy (SEM), was conducted to evaluate sperm morphology. At the same time, atomic absorption spectroscopy (AAS) determined the presence of heavy metals, including Zinc (Zn), Magnesium (Mg), Lead (Pb) and Cadmium (Cd), known to affect sperm production. Our findings revealed that long-term exposure to air pollution adversely affects sperm quality, manifesting in alterations during the spermatogenesis cycle, morphological abnormalities observed through SEM, and impaired sperm motility. Additionally, epidemiological evidence suggests that elevated levels of cadmium and lead in the environment induce oxidative stress, leading to sperm DNA damage and reduced sperm concentrations. These results underscore the urgent need for environmental interventions to mitigate air pollution and protect reproductive health.

Keywords: Air pollution; Atomic absorption spectroscopy (AAS); Heavy metals; Infertility; Spermatogenesis.

Graphical abstract

Fig. 1

Andrological profile showing semen type and the number of patients.

Fig. 2

Makler counting chamber.

Fig. 3

Graph indicating the occupation and number of patients. AST – Asthenoteratozoospermia, AZO – Azoospermia, NOR – Normozoospermia, SOATS – Severe Oligo Asthenoteratozoospermia, TERT – Teratozoospermia.

Fig. 4

Morphological changes in sperm cells.

Fig. 5

SEM images of sperm cells. A) Sperm cells with abnormal morphology, B) sperm cells with debris and contamination, C) sperm cells with acrosome defects.

Fig. 6

Graph indicates the concentration of zinc (Zn) in different human semen samples.

Fig. 7

Graph indicates the concentration of magnesium (Mg) in different human semen samples.

Fig. 8

Graph indicates the concentration of cadmium (Cd) in different human semen samples.

Fig. 9

Graph indicates the concentration of lead (Pb) in different human semen samples.