The ubiquitous use of plastic in our modern world and inadequate management of plastic waste has led to increased contamination of freshwater, estuary and marine environments. The U.N. Food and Agriculture Organization (FAO) estimated that in between 4.8 million to 12.7 million metric tons (tonnes) of plastic waste finds it way into our oceans each year. This represents 1.5%-4% of all non-fiber plastic manufactured and that number continues to grow each year.
Much of that waste is micro-plastic, defined as plastic items measuring less than 5 mm in their longest dimension. Plastic items may be manufactured within this size range (primary micro-plastics) or result from the degradation and fragmentation of larger plastic items (secondary micro-plastics). In 2009 an Australian study found the majority of facial cleansers, many tooth pastes, hand creams, body wash contained exfoliating beads made of polyethylene. These bits of polyethylene plastic ranging in size from roughly 5μm to 1mm do not biodegrade out in nature.
These microbeads are used in hundreds of products including cosmetics, sunscreen, body wash, toothpaste, skincare, and industrial and household cleaning products, and are too small to be captured by wastewater treatment plants filtration systems that were not designed to address such small contaminants. So, these microplastics beads flow down the drain and through waste water treatment plant and end up in our rivers, bays and oceans, where they may become a hazard to marine life. The polyethylene beads float and their scrubbing surfaces pick up contaminants which are consumed by marine life.
Scientists now believe that microplastics are consumed by marine life and can cause cellular necrosis, inflammation and lacerations in the digestive tracts of fish. Additionally, microplastics can pick up and accumulated chemical contaminants on their surfaces including priority pollutants under the US EPA Clean Water Act. This mixture of plastic and chemicals can accumulate in animals that eat them causing liver toxicity and disruption in the endocrine system, and possibly contributing to the intersexed fish that have appeared in rivers.
A new cleverly designed study for his dissertation Matthew Savoca a 2017 PhD from the University of California, Davis and now of the NOAA Southwest Fisheries Science Center in San Diego, California found that ocean-born plastic has a smell that marine animals finds appealing and are consumed preferentially.
Scientists believe that microplastics consumed by marine life can cause cellular necrosis, inflammation and lacerations in the digestive tracts of fish. Additionally, microplastics can pick up and accumulated chemical contaminants on their surfaces. Though, these adverse effects of microplastics ingestion have only been observed under laboratory conditions, usually at very high exposure concentrations that exceed present environmental concentrations by several orders of magnitude. In wild aquatic organisms microplastics have only been observed within the gastrointestinal tract, usually in small numbers, and at present there is no evidence that microplastics ingestion has had negative effects on populations of wild and farmed fish and shell fish.
Microplastics contain a mixture of chemicals added during manufacture. These additives efficiently sorb (leach or absorb) persistent, bio-accumulative and toxic contaminants from the environment. The ingestion of microplastics by fish and marine life and the accumulation of persistent bio-accumulative and toxic chemicals are the main perceived hazard and risk of micro-plastics in the marine environment. It is not known how much, if any, of the chemicals in the plastic leach out of the plastic and enter the food chain.
In humans the risk of micro-plastic ingestion is reduced by the removal of the gastrointestinal tract in most species of seafood consumed. However, most species of bivalves and several species of small fish are consumed whole, which may lead to micro-plastic exposure. The U.N. FAO calculated a worst case estimate of exposure to microplastics after consumption of a portion of mussels (225 g) would lead to ingestion of 7 micrograms (µg) of plastic, which would have a negligible effect (less than 0.1 percent of total dietary intake) on chemical exposure to certain persistent bio-accumulative and toxic chemicals and plastic additives. The operative word is bio-accumulate.
Congress amended the Federal Food, Drug and Cosmetic Act (FD&C Act) by passing the Microbead-Free Waters Act. The new law bans tiny beads of plastic known as microbeads that have been added as abrasives to beauty and health products like exfoliating facial scrubs and toothpaste. Under the law, companies will have to stop selling products containing plastic micro-beads in their products by July 2019, but the first phase went into effect this past July.
Much of that waste is micro-plastic, defined as plastic items measuring less than 5 mm in their longest dimension. Plastic items may be manufactured within this size range (primary micro-plastics) or result from the degradation and fragmentation of larger plastic items (secondary micro-plastics). In 2009 an Australian study found the majority of facial cleansers, many tooth pastes, hand creams, body wash contained exfoliating beads made of polyethylene. These bits of polyethylene plastic ranging in size from roughly 5μm to 1mm do not biodegrade out in nature.
These microbeads are used in hundreds of products including cosmetics, sunscreen, body wash, toothpaste, skincare, and industrial and household cleaning products, and are too small to be captured by wastewater treatment plants filtration systems that were not designed to address such small contaminants. So, these microplastics beads flow down the drain and through waste water treatment plant and end up in our rivers, bays and oceans, where they may become a hazard to marine life. The polyethylene beads float and their scrubbing surfaces pick up contaminants which are consumed by marine life.
Scientists now believe that microplastics are consumed by marine life and can cause cellular necrosis, inflammation and lacerations in the digestive tracts of fish. Additionally, microplastics can pick up and accumulated chemical contaminants on their surfaces including priority pollutants under the US EPA Clean Water Act. This mixture of plastic and chemicals can accumulate in animals that eat them causing liver toxicity and disruption in the endocrine system, and possibly contributing to the intersexed fish that have appeared in rivers.
A new cleverly designed study for his dissertation Matthew Savoca a 2017 PhD from the University of California, Davis and now of the NOAA Southwest Fisheries Science Center in San Diego, California found that ocean-born plastic has a smell that marine animals finds appealing and are consumed preferentially.
Scientists believe that microplastics consumed by marine life can cause cellular necrosis, inflammation and lacerations in the digestive tracts of fish. Additionally, microplastics can pick up and accumulated chemical contaminants on their surfaces. Though, these adverse effects of microplastics ingestion have only been observed under laboratory conditions, usually at very high exposure concentrations that exceed present environmental concentrations by several orders of magnitude. In wild aquatic organisms microplastics have only been observed within the gastrointestinal tract, usually in small numbers, and at present there is no evidence that microplastics ingestion has had negative effects on populations of wild and farmed fish and shell fish.
Microplastics contain a mixture of chemicals added during manufacture. These additives efficiently sorb (leach or absorb) persistent, bio-accumulative and toxic contaminants from the environment. The ingestion of microplastics by fish and marine life and the accumulation of persistent bio-accumulative and toxic chemicals are the main perceived hazard and risk of micro-plastics in the marine environment. It is not known how much, if any, of the chemicals in the plastic leach out of the plastic and enter the food chain.
In humans the risk of micro-plastic ingestion is reduced by the removal of the gastrointestinal tract in most species of seafood consumed. However, most species of bivalves and several species of small fish are consumed whole, which may lead to micro-plastic exposure. The U.N. FAO calculated a worst case estimate of exposure to microplastics after consumption of a portion of mussels (225 g) would lead to ingestion of 7 micrograms (µg) of plastic, which would have a negligible effect (less than 0.1 percent of total dietary intake) on chemical exposure to certain persistent bio-accumulative and toxic chemicals and plastic additives. The operative word is bio-accumulate.
Congress amended the Federal Food, Drug and Cosmetic Act (FD&C Act) by passing the Microbead-Free Waters Act. The new law bans tiny beads of plastic known as microbeads that have been added as abrasives to beauty and health products like exfoliating facial scrubs and toothpaste. Under the law, companies will have to stop selling products containing plastic micro-beads in their products by July 2019, but the first phase went into effect this past July.
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