Sea Turtles and Their Eggs:
No Longer Safe Food
by Marina Fastigi
Why Sea Turtles are Important
Sea turtles play an important role in the marine ecosystem and our lives. Sea turtles’ diet includes jellyfish, which is the main diet for Leatherbacks; sea turtles therefore help control jellyfish populations. Did you know that jellyfish devour fish eggs and larvae, mostly those of yellowfin tuna? Relentless hunting of turtles and poaching of their eggs could drive turtles to extinction within the next ten years, and the consequences are clear: the demise of sea turtles causes the loss of important amounts of fish species consumed by humans.
Hawksbills protect reefs by feeding on sponges, clearing space for the formation of new coral colonies. Green turtles feed on sea grasses, keeping the beds short and healthy, thus providing shelter to hundreds of species of small fish and crustaceans. The decline of the Caribbean green turtles contributed to the die-off of sea grasses and the disappearance of coastal fish. Sea grasses protect the coastline from wave erosion thus stabilizing beaches. Loggerheads feed on crustaceans and discard the bits of shell in their feces; the disintegration of the shells increases the nutrient rate in the ocean-bottom ecosystems.
Ocean Life and Pollution
Stopping the harvesting and consumption of sea turtles and their eggs is important not only to contribute to the health of marine eco-systems, but also to preserve our own health. Sea turtles have been a traditional food supply for many peoples in the Caribbean, but recent research has shown that turtle meat is often heavily contaminated. By eating turtle meat or eggs we can put ourselves at risk of serious permanent health damage and even death.
Our oceans have been massively polluted with heavy metals, mercury in particular, for the past 40 years, due to chemical industrialization. Yearly, up to 6,000 tons of mercury are released into the environment. Coal-burning and chlor-alkali industries use mercury for producing chlorine (used in plastics, pesticides and PVC pipes). Incinerators burning waste, including our popular backyard burning of garbage containing plastics, release mercury into the air, land and water, ending up in our oceans.
Turtles, in their long migratory lives, accumulate in their bodies elevated levels of contaminants present in the marine environment: mercury, cadmium, POPs (Persistent Organic Pollutants) and a cocktail of different pesticides. Inorganic mercury, in contact with water organisms, becomes methyl-mercury, a highly toxic form of mercury. Small fish feed on tiny contaminated organisms; larger fish feed on small fish, accumulating mercury in their bodies; unable to expel these heavy metals through digestion, these remain in the organic system, poisoning it. High in the marine food-chain, migratory species such as the largest fish (tuna, swordfish, marlin, sharks, king mackerel, etcetera), dolphins, whales and turtles end up carrying very high concentrations of methyl-mercury in their flesh, blood, organs and eggs.
The Global Map of Human Impact on Marine Ecosystems (Science magazine, 15 February 2008) shows that the Caribbean Sea ranges from “Medium” to “Very High” impact in terms of pollution and overfishing. Fish-eating migratory species (including birds) have been tested and found to be highly contaminated even in the most remote areas of the planet, demonstrating that location is no longer a factor of safety from pollution. Pollutants are everywhere, spread through the food-chain process of sea and air creatures, winds and ocean currents.
Connecting the Dots of a Larger Picture
Since 2002, the Barbados Sea Turtle Project, the University of the West Indies and the Wider Caribbean Sea Turtle Conservation Network (WIDECAST), including the Kido Foundation, have being applying ID tags to nesting and foraging turtles to monitor their migrations. Some hawksbills nesting in the Eastern Caribbean (as well as green turtles that forage there) travel to the heavily polluted Gulf of Mexico, and our southern-born leatherbacks travel as far north as Nova Scotia, Canada and across the Atlantic to Britain’s coastal waters.
Tuna is today a highly contaminated fish. In the USA and Europe, labels on large fish packages in supermarkets warn consumers of possible health risks. According to an article in the September 16th, 2006 issue of New Scientist magazine, the level of cadmium in sea turtles measures three times higher and mercury ten times higher than in tuna!
High levels of cadmium, aluminum, chromium, lead, silver, mercury and titanium were found in tissue samples taken from nearly 1,000 whales over a five-year period, from polar to equatorial waters. Mercury as high as 16 parts per million was found in these whales. Mercury-high fish (shark, swordfish), which health experts warn children and pregnant women to avoid, typically have levels of about one part per million.
The World Health Organization and EU have set allowable concentrations of the banned pesticide DDT and its breakdown products in food at no higher than 50 ppb (parts per billion). Sea turtles in the Atlantic have showed concentrations of breakdown products of DDT as high as 1,200 ppb.
Medical researchers warn of the insidious effects that mercury toxicity may cause to the brain development of unborn babies and younger children. Effects include neuro-developmental diseases, mental retardation, attention deficit disorder and autism. Other serious risks for children and adults are neurotoxicity, kidney disease and liver cancer.
Diseases and symptoms induced by mercury poisoning include chronic fatigue, fibromyalgia, depression, anxiety, obesity, dementia, Parkinson’s disease, cancer, heart failure and heart disease, memory problems, Alzheimer’s, amyotropic lateral sclerosis, multiple sclerosis, encephalopathy (non-specific brain malfunction), inability to concentrate, tremors, loss of balance, impaired hearing, tunnel vision, slurred speech, headaches, muscle pain and twitches, insomnia, digestive problems and food allergies.
Aphrodisiac or Impaired Sexual Function?
Sea turtle products have been prescribed over the centuries as remedies for anemia, asthma and respiratory problems and, in the Caribbean, sea turtle eggs are traditionally claimed to be an aphrodisiac, consumed mainly by males hoping to boost their sexual performance. According to doctors, the opposite is true: the high concentrations of cholesterol and pollutants in turtle eggs may impair sexual performance and lower fertility; namely, it is the very consumption of turtle eggs that likely caused the embarrassing physical failure in the first place!
Poisoning and Deaths
Reported globally, cases of poisoning and deaths (especially among children) from eating sea turtle meat, organs and eggs and drinking turtle blood, reveal the seriousness of the problem. In June this year, in Thailand, three persons died of chelonitoxism from ingesting Hawksbill turtle meat: a village woman, an 11-month-old boy breast-fed by his mom who had eaten the same turtle meat, and a 60-year-old woman. Dozens of those who shared that turtle meat also suffered from symptoms including respiratory difficulty, stomach pain, nausea, vomiting, fever and double vision, but survived. In the Solomon Islands six children died out of the 28 people affected within five days of eating turtle meat.
Based on the mortality statistics related to turtle poisoning, the public — in particular women of childbearing age, nursing mothers and small children — should be discouraged from consuming any sea turtle products. Though turtles may appear healthy, there is a high risk that they carry internal tumors or dangerous bacteria and are contaminated with methyl-mercury, cadmium, POPs and pesticides.
Tumors Affecting Sea Turtles
Turtles too suffer from the pollutants they ingest and increasingly develop fibropapillomas (tumors or cancerous growths), which affect humans as well. On March 21st, 2007 in Carriacou, a mature Green turtle with a four-inch fibropapilloma bulging over her right eye was purchased alive by Kido Foundation at the fish market, thus preventing her contaminated meat from being sold to the unsuspecting public. This turtle had several smaller tumors on her neck, flippers and plastron. An inquiry among fishermen revealed that it was not the first sea turtle with fibropapillomas to be sold to the public in Carriacou.
International fisheries records show that sea turtles worldwide are afflicted with fibropapillomas. First seen on Green turtles in the 1980s, this type of tumor has now spread to other turtle species. It grows on soft tissues, eyes and mouth, through the carapace and plastron (belly), on lungs, kidneys, liver and intestines.
Bacteria Present in Sea Turtles
Ongoing studies show that sea turtles and eggs carry bacteria: mycobacteria (which may cause TB), salmonella, vibrio (may cause cholera), E-coli, chlamydia (causing a pneumonia-like disease) leptospira, arsenic and potentially lethal toxins from ingesting algal blooms (‘red tides’).
Data from 2003 - 2004 showed that 80 percent of the samples of Green turtles in Baja California exhibited high antibody levels of leptospirosis. People infected with leptospirosis often show no symptoms, but left untreated, it can cause kidney damage, meningitis, liver failure, respiratory distress or death.
Cooking may kill bacteria and fungi (although it is very difficult to eliminate bacteria from your hands and tools after handling raw meat), but cooking does not eliminate the harmful toxins, which once ingested remain in our bodies. It is important to underline that cooking turtle meat or eggs cannot get rid of heavy metals.
Proposal for the Immediate Future
Common sense and deep concern for public health, as well as basic environmental conservation, suggest that authorities in charge need to establish a moratorium for hunting sea turtles in each Caribbean state, banning the trade and consumption of turtle products. It is also strongly suggested that authorities and the media duly inform the public of the health hazards associated with the consumption of sea turtles and eggs, as well as of other contaminated ocean creatures, which may expose us and future generations to serious health hazards.
Marina Fastigi, Ph.D. is Director of Kido Foundation, a not-for-profit organization in Carriacou, Grenada. “Sea Turtle as Food is a Health Hazard for Consumers” is a Kido public awareness campaign, supported by the World Society for the Protection of Animals (www.wspa-international.org). For more information call (473) 443-7936 or e-mail firstname.lastname@example.org.
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