Polars bears health threatened by toxic chemicals
Evidence proving that polar bears are being harmed by industrial toxic chemicals present in water and soil has emerged this week.Toxic substances already outlawed by the EU such as polychlorinated biphenyls (PCBs) (see related story) and some pesticides have contaminated polar bears and are already affecting them in a negative way, according to research by conservation organisation, WWF.
Even though the toxins showing up in these studies are no longer widely used in manufacturing processes or in farming, they are slow to break down in the environment and consequently can remain present in water, ice or soil for many years.
"The studies conducted on polar bears over the last few years all conclude that these animals are negatively affected by chemical pollution," stated Dr Andrew Derocher, a contributor to all the recent studies on polar bear contamination (see related story). "Most polar bears have several hundred man-made chemicals in their bodies and have never evolved mechanisms to deal with them."
Dr Derocher added that the unintentional tinkering with the animals' hormone and immune systems was very harmful to them. High levels of PCBs, for instance, lowered the number of antibodies in their blood, which then left the polar bears more susceptible to infection, according to the report. It also demonstrated how altered hormone levels could result in diverse negative health impacts, including development, behavioural and reproductive problems.
Even though some damage had already been done, other harmful chemicals needed to be outlawed from industrial use, according to Brettania Walker, toxics officer in WWF's Arctic programme, in order to reduce harm inflicted on polar bears, amongst other animals, and the environment.
"Other contaminants with similar properties to already banned chemicals continue to be used on a day-to-day basis in manufacturing processes and products throughout the world. It is crucial to prevent these newer-generation chemicals from accumulating in, and polluting, the environment," Ms Walker said.
Most chemicals on the market today have not been adequately tested to determine their impacts on human and wildlife health, Ms Walker added. She stated that there is an urgent need for safer chemical legislation, including a strong and protective version of the EU's REACH legislation, currently under debate (see related story), to help protect all species from nasty chemical side effects.
By Jane Kettle