PAH's and Fish, a scary scenario

A recent article from the National Oceanic and Atmospheric Administration (NOAA) Fisheries has indicated that recent oil spill in the Gulf of Mexico affected the developing hearts of tuna (http://www.nmfs.noaa.gov/stories/2014/03/3_24_14oil_spill_effects_large_marine_fish.html). The reason for the abnormalities stems from crude oil, which contains polycyclic aromatic hydrocarbons (PAHs). Often for embryos or developing organisms the threshold for defects is much lower than that of adults. In the case of the tuna affected, the threshold is already very small, 1-15 ppb. Many of the affected fish died soon after hatching, while some may also have survived with less severe developmental issues. However those that survive will have a higher level of PAHs in their body, possibly leading to bioaccumulation and ingestion in humans. The PAHs released from crude oil spills are stored in the fatty tissues of many marine organisms which can then be consumed by humans, or build up to toxic levels and kill the organisms.

A pressing matter is the effect of these PAHs. There are shown carcinogenic properties of PAHs in test animals and is considered to be a probable human carcinogen as well.  Since PAHs are common water pollutants, bioaccumulation in organisms that become seafood is a serious issue. One of the most well known carcinogenic PAH is benzo[a]pyrene. The key feature of PAH carcinogens is a “bay region” which allows for continued reactions in the metabolic processes of the body that result in a carcinogen.

While the chemistry behind the topic is interesting I think the main point is that we, as a society, need to be more careful and conscience as to what we are polluting our environment with. Pollutants do not just affect one area, but rather spread and contaminate areas that had no influence over the contamination in the first place. We have been lulled into a tragedy of the commons mindset, whereby we stand by while animals and humans are seriously affected.