Polychlorinated biphenyls (PCBs) were banned in 1979 because they were found to be highly toxic, causing cancers in animals and humans.
PCBs also contaminated seawater, researchers in the UK found. Mammals like dolphins and whales accumulated the toxic chemicals, affecting their fertility. An orca was found to contain 1,300 mg/kg, while only 50 mg is enough to harm the reproductive and immune systems. The chemicals were used in colored plastics, electrical equipment, and even bottles.
Although PCBs have been banned, they are still used secretly in some parts of the world. They also take a long time to decompose. Their effects show us the importance of avoiding chemicals with long-term environmental impacts. Even in a landfill they can seep into the soil, reach a water source and go into the sea. We must strive to avoid adding to the pollution already in ecosystems.
Credit: https://edition.cnn.com/…/orca-killer-whale-pol…/index.html… และ www.thaihealth.or.th
Become part of conserving marine and coastal resources with Blue Carbon Society