Plastic wrap,cling film,Saran wrap,cling wrap,Glad wrap orfood wrap is a thinplastic film typically used for sealingfood items in containers to keep them fresh over a longer period of time. Plastic wrap, typically sold on rolls in boxes with a cutting edge, clings to many smooth surfaces and can thus remain tight over the opening of a container withoutadhesive. Common plastic wrap is roughly 0.0005 inches (12.7 μm) thick.[1][2] The trend has been to produce thinner plastic wrap, particularly for household use (where very little stretch is needed), so now the majority of brands on shelves around the world are 8, 9 or 10 μm thick.
Plastic wrap was initially[when?] created frompolyvinyl chloride (PVC), which remains the most common component globally. PVC has an acceptably-low permeability to water vapor and oxygen,[3] helping to preserve the freshness of food. There are concerns about the transfer ofplasticizers from PVC into food.[citation needed]Pliofilm was made of various kinds of rubber chloride. Used in the middle of the 20th century, it could be heat-sealed.[4]
A common, cheaper alternative to PVC islow-density polyethylene (LDPE). It is less adhesive than PVC, but this can be remedied by addinglinear low-density polyethylene (LLDPE), which also increases the film'stensile strength.[5]
In the US and Japan, plastic wrap is sometimes produced usingpolyvinylidene chloride (PVdC), though some brands, such asSaran wrap, have switched to other formulations due to environmental concerns.[6]
The most important role plastic wrap plays infood packaging is protection and preservation. Plastic wrap can prevent food from perishing, extend its shelf-life, and maintain the quality of food. Plastic wrap generally provides protection for food from three aspects: chemical (gases, moisture, and light), biological (microorganisms, insects and animals), and physical (mechanical damage). In addition to food protection and preservation, plastic wrap can also reducefood waste, tag food information, ease the distribution processes, and increase product visibility and microwavability.[7]
Plastic materials are widely used in the food industry due to their low price and convenience; however, there has been an increased health concern because of the possibility of releasing undesirable chemicals from plastic materials into food products. Plastic packages are made of various materials such as polyethylene, low-density polyethylene, etc. Additives, includinglubricants,plasticizers,UV-absorbers,colorants, andantioxidants, are added into plastic materials in order to improve the quality and properties of the plastics. Besides, plastic materials are often coated and printed in the final processes, in which inks andvarnishes are used. Although the barrier properties of the plastic packages provide protection of foods from external contaminations, the additives and coating materials in the plastic packages are able to penetrate into foods and cause health-related issues.[8]
"It is true that substances used to make plastics can leach into food," says Edward Machuga, Ph.D., a consumer safety officer in theFDA'sCenter for Food Safety and Applied Nutrition. "But as part of the approval process, the FDA considers the amount of a substance expected to migrate into food and the toxicological concerns about the particular chemical." A couple of cases have caught media attention in recent years. One case is in regard todiethylhexyl adipate (DEHA). DEHA is a plasticizer, a substance added to some plastics in order to make them flexible. There are public concerns about DEHA exposure while consuming food with plastic wraps. There are potentials of exposure to DEHA; however, the levels of the exposure are much lower than the no toxic effect levels in animal studies. Another case is in regard to the dioxins, labeled as "likely human carcinogen" by the Environmental Protection Agency. The public has been misled by the claims that plastics contain dioxins[citation needed], while Machuga stated that no evidence that shows plastic containers or films contain dioxins was seen by the FDA[citation needed]. According to writing in FDA Consumer Magazine as of November 2002, when used properly the use of plastic wrap in food preparation does not pose danger to human health.[9]
The accumulation ofplastic debris on the Earth is seen as a threat to both wildlife and the environment. Plastic debris might choke or trap wildlife, and it could also penetrate toxic compounds into ecosystems. This land-originated problem has become a problem in ocean ecosystem as well since streams and rivers which are close to the land have carried the plastic debris into the coast, and currents transfer it to everywhere in the ocean. Plastic debris is a potential danger to all forms of aquatic life. Some marine species, like sea turtles, take plastic as prey items by mistake. Also, some species might even pick up plastics to feed their offspring, which cause huge problems on growth and even cause mortality. Toxic compounds in plastics can disrupt hormone regulation in the cells of organisms, which can lead to alteration of animals' mating behavior, reproductive ability, and even cause the development of tumors.[10]
A study shows that using recycled plastic materials can reduce the environmental impacts significantly as a result of minimizing exploration, mining and transportation of natural gas and oil. One of the possible ways to increase the recycling rate is adding fibrous reinforcement into plastics. The environmental impact has been assessed using the life cycle assessment method. The results showed that plastics with fibrous reinforcement added can sharply reduce resource usage and global warming in civil applications.[11]
Media related toCling film at Wikimedia Commons
