Sources and Occurrence of Nano Particles in Aquatic Ecosystems

Introduction

The usage of plastics and polymer composites is on the rise in the construction and other sectors. Plastics manufacturing is expected to reach 300 million metric tonnes per year over the world. The European Union's plastic demand in 2010 was projected at 46.4 million tonnes, with the majority of that demand coming from the packaging of food and consumer goods, as well as from the construction sector (Plastics Europe 2013). Around 24.7 million metric tonnes of plastic garbage enters the waste stream each year, with a recycling rate of 57.9 percent. This includes littering, dumping trash in landfills, and using the sewage system to dispose of the garbage. Between 4.8 and 12.7 million tonnes of plastic debris were released into the ocean in 2010, according to the study by Jambeck et al. Although these numbers are disturbing in terms of volume, it is not yet understood how much impact these substances cause to human health. In the food packaging business alone, plastic is consumed at a rate of 14.5 million tonnes annually. It's good to know that better packaging for food may help prevent bacterial illnesses, including Salmonella and other food borne diseases, while also reducing food waste and making it easier to distribute it. It is thought that human populations are exposed to pollutants associated with plastics mostly via food packaging migration (Grob et al. 2006), even though testing has only been conducted on a small proportion of the chemicals present (Claudio 2012). It is not apparent how food-contact compounds may be protected after they have been thrown away in the trash.

Chronic exposure to plastics and their additives can't be quantified because of the lack of data on rates of degradation and fragmentation, chemical leaching into environmental matrices, and entrance into the food chain. As a possible solution to this issue, scientists can discover the substances that make up the human body. Blood, breast milk, saliva, or urine may be used for human biomonitoring since they include concentrations of environmental pollutants and their metabolites. Environmental exposures may be accessed via biomonitoring, which is regarded the gold standard since it provides an integrated evaluation of an individual's exposure to pollutants from different sources (Sexton et al. 2004). This method has shown that chemicals used in plastics manufacturing are definitely present in the human population's body fat and urine. Public health concerns have been raised by the ubiquitous availability of several substances in the general population at amounts that have been shown to cause damage in animal models (Talsness et al. 2009; Melzer and Galloway 2010). Involving 345 investigations, the National Health and Nutrition Examination Survey (NHANES) is the largest and most extensive human biomonitoring project ever done in the United States (https://www.cdc.gov/nchs/nhanes.htm). Bisphenol A, phthalates, styrene, acrylamide, triclosan, and brominated flame retardants are among the chemicals studied by NHANES, and their prevalence in the general population is an important consideration for this research.

To increase their physical qualities, plastics may include complicated combinations of additives that leak from the polymer into the surrounding environment. There is the prospect of continual chemical diffusion from the core of the plastic particle to the surface of the particle, which will lead to leaching. Despite the fact that most chemicals aren't persistent and have limited half lives in the body, leaching from plastic particles might be a long-term source of toxins in tissues and bodily fluids (Engler 2012). Phthalates, bisphenol A, brominated flame retardants, triclosan, bisphenone, and organotins are some of the plastics additives that are harmful to human health and should be avoided at all costs.

Legislation has been enacted to control the possible migration of polymer components and additives into food and beverages because of their potential impact on human health. Typically, migration levels are estimated from measurements using different solvents to simulate the receiving environment or can be estimated using partitioning models that consider aspects such as the desportion rates from the polymers, dimensions of the polymer framework, and dimensions of the diffusing molecules (Helmroth et al. 2002).