Articles

Sabtu, 24 Januari 2009

Safety issues

The fishing industry is hazardous for fishermen. Between 1992 and 1999, US commercial fishing vessels averaged 78 deaths per year. The main contributors to fatalities are:

* inadequate preparation for emergencies
* poor vessel maintenance and inadequate safety equipment
* lack of awareness of or ignoring stability issues.

Many fishermen, while accepting that fishing is dangerous, staunchly defend their independence. Many proposed laws and additional regulation to increase safety have been defeated because fishermen oppose them.

Alaska's commercial fishermen work in one of the world's harshest environments. They endure isolated fishing grounds, high winds, seasonal darkness, very cold water, icing, and short fishing seasons, where very long work days are the norm. Fatigue, physical stress, and financial pressures face most Alaska fishermen through their careers. The hazardous work conditions faced by fishermen have a strong impact on their safety. Out of 948 work-related deaths that took place in Alaska during 1990-2006, one-third (311) occurred to fishermen. This is equivalent to an estimated annual fatality rate of 128/100,000 workers/year. This fatality rate is 26 times that of the overall U.S. work-related fatality rate of approximately 5/100,000 workers/year for the same time period.

History

Fishing has existed as a means of obtaining food since the Mesolithic period. By the time of the Ancient Egyptians, fishermen provided the majority of food for Egyptians. Fishing had become a major means of survival as well as a business venture. Fishing and the fisherman had also influenced Ancient Egyptian religion; mullets were worshiped as a sign of the arriving flood season. Bastet was often manifested in the form of a catfish. The method Amun, in ancient Egyptian literature, created the world, is associated with the Tilapia's method of mouth-brooding.

Commercial fishing

According to the FAO, there were 38 million commercial and subsistence fishermen and fish farmers in 2002, more than triple the number in 1970. Of this total, 74% worked in capture fisheries and 26% in aquaculture. The total fishery production of 133 million tonnes equated to an average productivity of 3.5 tonnes per person.[2]

Most of this growth took place in Asian countries, where four-fifths of world fishers and fish farmers dwell.

Most fishermen are men involved in offshore and deep-sea fisheries. Women fish in some regions inshore from small boats or collect shellfish and seaweed. In many artisanal fishing communities, women are responsible for making and repairing nets, post-harvest processing and marketing

Mercury content

Fish and shellfish have a natural tendency to concentrate mercury in their bodies, often in the form of methylmercury, a highly toxic organic compound of mercury. Species of fish that are high on the food chain, such as shark, swordfish, king mackerel, albacore tuna, and tilefish contain higher concentrations of mercury than others. This is because mercury is stored in the muscle tissues of fish, and when a predatory fish eats another fish, it assumes the entire body burden of mercury in the consumed fish. Since fish are less efficient at depurating than accumulating methylmercury, fish-tissue concentrations increase over time. Thus species that are high on the food chain amass body burdens of mercury that can be ten times higher than the species they consume. This process is called biomagnification. The first occurrence of widespread mercury poisoning in humans occurred this way in Minamata, Japan, now called Minamata disease.

The complexities associated with mercury transport and environmental fate are described by USEPA in their 1997 Mercury Study Report to Congress. Because methylmercury and high levels of elemental mercury can be particularly toxic to unborn or young children, organizations such as the U.S. EPA and FDA recommend that women who are pregnant or plan to become pregnant within the next one or two years, as well as young children avoid eating more than 6 ounces (one average meal) of fish per week.

In the United States the FDA has an action level for methyl mercury in commercial marine and freshwater fish that is 1.0 parts per million (ppm), and in Canada the limit for the total of mercury content is 0.5 ppm. The Got Mercury? website includes a calculator for determining mercury levels in fish.

Species with characteristically low levels of mercury include shrimp, tilapia, salmon, pollock, and catfish (FDA March 2004). The FDA characterizes shrimp, catfish, pollock, salmon, and canned light tuna as low-mercury seafood, although recent tests have indicated that up to 6 percent of canned light tuna may contain high levels.