The consumption of fish and seafood is a contentious issue at the best of times; even vegetarians do sometimes eat fish due to both the fact that fish seem further removed [than mammals] from our idea of sentient beings, and also because we know that Essential Fatty Acids (EFAs) are needed for human health. But I think there are some very real health and ethical reasons to completely stop eating fish and other seafood right now, particularly for people who do actually eat fish regularly.
Why? Well, because the oil leak in the Gulf of Mexico is substantial.
I won't pretend to know much about how to stop the leak (I'm sure there are already ample armchair experts). However, even once it is stopped we will still have a significant clean-up job on our hands, and the pollution will remain for some time.
Obviously the US government will not allow fishing in the water that is being directly affected by the oil spill, but that does not mean that we are 'off the hook' so to speak.
We have two serious issues to examine when we decide whether we are comfortable eating fish and shellfish: firstly what types of toxins could find their way into seafood, and secondly what would be the effects of overfishing in the remaining good fishing locations to make up for the shortfall in the supply of fish?
In terms of toxins, we have a number of different substances polluting oil affected waters which have the ability to build up in fish and shellfish. Firstly we have crude oil and secondly we have the dispersant being used, currently Corexit 9500. Corexit 9500 is a highly poisonous substance, roughly four times more poisonous than oil. Crude oil contains both mercury and lead, which are highly poisonous heavy metals. Crude oil also includes benzene, toluene and polynuclear aromatic hydrocarbons (PAH), all of which have been recognised as causing cancer. Research is being conducted as to whether PAH can accumulate in fish, but at the very least it has been shown that it does accumulate in shellfish.
Fish will absorb pollutants from the water through their respiratory systems. These toxins will not be removed from the fish's bodies as quickly as they are being received and so the poisonous substances such as mercury and lead tend to build up. In addition, some fish are predatory and so these larger fish will have both their own accumulated environmental poisons and those accumulated from the smaller fish. In this way, toxins increase up the food chain and it is the largest, most toxic fish that are typically fished for human consumption.
Mercury is associated with brain impairments, both degenerative in adults and the development of autism and chromosomal disorders (such as Down's syndrome) in children. Mercury crosses the placenta in pregnant mothers and has its greatest effect on babies and children due to being significantly more concentrated.
Lead affects the nervous system, brain, kidneys and reproductive system. In children it has been associated with low IQ, slow growth and hearing defects. In laboratory tests on animals, no minimum quantity of lead has been considered a safe dose; even the smallest quantities have had a harmful effect.
Corexit 9500 is BP's oil dispersant of choice, but was reputedly banned in Britain over a decade ago due to its highly toxic affects on both the environment and people. It is both more toxic and less effective than other chemical dispersants, requiring a larger application in order to be effective.
The use of Corexit 9500 in such quantities and at such oceanic depths is unknown in human history, and the exact contents of the mixture are a trade secret. Corexit 9500 increases in toxicity as it heats up, and oil in the water tends to increase the temperature of the water. It is expected that it will affect humans' respiratory systems, nervous systems, livers, kidneys and also cause blood disorders. Just as with mercury and lead, Corexit 9500 will have a greater impact on children due to their smaller size. At the time that this article was written (early June 2010) over 600,000 gallons of Corexit 9500 have been applied to the ocean's surface.
Clearly the sea-creatures living in and around the Gulf of Mexico are going to be off the menu for some time. The government won't willingly allow people to eat contaminated seafood right?
Unfortunately however, the Gulf Coast is responsible for about 50% of the total US harvest in its peak season. Fishing in the Gulf of Mexico is estimated to be worth $2.4 billion per year. Not only is fishing an essential part of USA's GDP, but people are still eating fish and so the demand causes pressure on other fishing localities to increase the supply.
In addition, many fish, particularly deep ocean fish are migratory and will pass through the Gulf of Mexico waters on their way to someplace else. Some fish will travel up to 200 miles for feeding and reproduction and so it is not possible to easily determine which fish will have been affected by the growing pollution.
Health issues aside, there is a secondary issue which will begin to affect other fishing areas. That is overfishing. Overfishing is when commercial fishing operations catch so many fish that the remaining population of fish are not able to increase their numbers enough to replace the number that have been caught. As it is, overfishing has already been a global issue for some time and according to overfishing.org, almost 80% of the world's fisheries are fully to over-exploited, depleted or in a state of collapse, and over 90% of the stocks of large predatory fish stocks are already gone. If we do not do something about it, we are approaching a situation where some fish may become endangered species. By increasing demand for fish from areas that normally have fewer fish numbers, we are simultaneously speeding up the rate at which the population of fish from that area declines.
It is not only the fish that are affected by overfishing, sea birds and mammals both eat fish, and as the number of edible fish become harder to find, these animals are being increasingly caught in fishing hauls, killed and discarded.
So while those of us who are not yet affected by the disaster in the USA can sit back and watch everything unfold, it will be our fish stock that will be systematically removed from the oceans to make up for the shortfall in US fishing.
In my opinion, the only healthy and ethical thing to do about the seafood issue is to completely stop eating fish and their byproducts. We need to look into getting our EFAs from other sources such as flaxseeds, spirulina, chlorella and phytoplankton. Fortunately fish do not create their own EFAs, but instead break down the EFAs in the microalgae food that they consume. Humans are able to do the same, and so we can replace fish in the diet with supplemental sources of EFA. I have previously used fish oil for DHA supplementation, but I am going to try out some vegan alternatives.
Want to find out more about health, then visit Petra Smirnoff's site on how to choose the healthiest diet for your needs.