Research analysing 53 samples of human breast milk found that silica and metal nanoparticles were present in 42 of them. The study, published in PNAS, identified the mechanisms of nanoparticle infiltration from oral or respiratory exposure into blood vessels and subsequent accumulation in breast milk.
Up to 1.4 billion people may be living in areas with soil contaminated by heavy metals such as arsenic, cadmium, cobalt, chromium, copper, nickel and lead, according to research published in Science. The paper, which used data from more than 1,000 studies, estimates that 14-17% of farmland worldwide could be contaminated by at least one toxic metal. Cadmium is the most widespread, especially in South and East Asia, parts of the Middle East and Africa.
Research published in JAMA Network Open suggests that exposure to common environmental toxicants is associated with depressive symptoms. The authors analysed data from urine or blood samples from more than 3,400 US adults and found that 27 environmental toxicants were associated with these symptoms, which could be linked to inflammatory processes.
Heavy metals - including arsenic, cadmium and mercury - may adversely affect the ovaries of women approaching menopause, a study claims. Those with high levels of metals in their urine had lower levels of anti-Müllerian hormone, indicating diminished ovarian reserve - fewer oocytes in the ovaries compared to other women of that age. The authors, whose study is published in The Journal of Clinical Endocrinology & Metabolism, used urine data from more than 500 women in the US up to 10 years before their last menstrual period.