Wednesday 26 June 2019 ,
Wednesday 26 June 2019 ,
Latest News
  • DU tests find detergent, antibiotics in cow’s milk
  • Convince Myanmar to take Rohingyas back, PM tells China
  • World Cup: Australia crush England to reach WC semi-finals
  • Bangladesh needs to treat over 1.5m new TB cases in next 5yrs
  • BSMMU performs first-ever liver transplant surgery
22 June, 2018 00:00 00 AM
Print

Toxic effects of plastic food packaging

By Ayesha Mosharraf
Toxic effects of plastic food packaging

Sustainable green packaging is nowadays a most talked about term which is used for materials that have low or negligible impact on the environment and also on public health. Packaging has become an indispensable part of our daily life as proper packaging allows food protection from physical, chemical or microbiological contamination. It also plays a vital role in preservation of food quality, minimising food waste and reducing preservatives used. Any compromise with the packaging leads to health hazards by contamination.

One of the most momentous applications of plastics is in the food packaging sector which was first introduced in 1957 as a simple sandwich bag. Plastic food packages (PFPs) occupied over 25 to 30 percent of the bread packaging market in 1966. PFPs were rapidly popularised commercially in the 1980s due to a combination of flexibility, strength, lightness, stability, impermeability and ease of sterilization. Lately, it has replaced all traditional food bags.

PFP does not affect the taste and quality of the foodstuff. In fact, the barrier properties of plastics ensure that food keeps its natural taste while protecting it from external contamination. Moreover, its unparalleled versatility is demonstrated in a multitude of applications. PFP hygienically protects and preserves perishable food for longer by maintaining the taste and nutritional value of food.  

Numerous forms of PFPs are broadly used in the world such as polythene bags, wrapping, bottles, rigid containers, caps and lids. From airtight wraps to shelf stable bottles and containers, plastic packaging plays a key role in delivering a safe food supply, from farm to table and is a material of choice for freezing food for longer term storage. Besides, modified atmosphere packaging helps preserve food freshness and can extend a product’s shelf life by slowing the growth of bacteria.

The major types of plastic resins used in PFPs such as polyethylene terephthalate (PET), high-density polyethylene (HDPE), polyvinyl chloride (PVC), low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS) and polycarbonate (PC). Among them, PET is a lightweight plastic that is made to be semi-rigid or rigid which makes it more impact resistant, and helps protect food. HDPE is a hard, opaque plastic that is lightweight but also strong. PVC is a common type of plastic that is biologically and chemically resistant. LDPE is thinner than some other resins and also has high heat resilience. PP is somewhat stiff but less brittle than some other plastics. PS is a colourless, hard plastic without much flexibility.

In food packaging, PET is commonly used for soft drinks, sport drinks, single-serve water, ketchup, salad dressing, vitamins, vegetable oil bottles and peanut butter containers. HDPE is used for juice and milk jugs, squeeze butter and vinegar bottles, and chocolate syrup containers, as well as grocery bags. PVC is used as packaging for tamper-resistant over-the-counter medications, along with shrink wrap for a variety of products. LDPE is used to make coffee can lids, bread bags, six-pack soda can rings, including fruit and vegetable bags. PP is used to make yogurt containers, maple syrup containers, cream cheese containers, sour cream containers, and prescription drug bottles. PS is used to make plastic cups, deli and bakery trays, fast food containers, lids, hot cups and egg cartons.

The PFP service life length is very short and so a large volume of discarded PFPs are generated daily. But PFPs are non-biodegradable and contain toxic chemicals such as BisphenolA (BPA), phthalates and PVC. Furthermore, toxic heavy metals such as lead, chromium, cadmium and mercury are added in PFPs as additives. Food contact of toxic materials of PFPs contaminates packed food and ultimately effect consumer’s health. Further, lack of degradability and the closing of landfill sites, as well as growing water and soil pollution problems associated with discarded PFPs have led to concern about plastics.

In recent years, biofibres have attracted increasing interest due to their wide applications in food packaging. As a result, several types of biopolymers have been invented worldwide; such as polylactide (PLA), polyhydroxybutyrate (PHB), and polyhydroxyalkanoate (PHA) that are increasingly becoming available for use in food packaging. Again, PHB has several polymer classes - P3HB, P4HB, PHV, PHH, PHO, and their co-polymers which quality is almost same as polyethylene (PE), PP and PS. Improved production of PHB has required manipulation of promoters driving expression of transgenes, reduction in activity of endogenous enzymes in competing metabolic pathways, insertion of genes to increase carbon flow to green polymer.

The most important bio-based plastics on the market are the PLA produced from Nature Works (USA) and the Mater-Bi, a starch based bioplastics, made from Novamont (Italy). Compostable plastic materials, produced from PLA, corn starch, or sugarcane degrade in a green yard-waste compost environment. PHA has attracted attention as environmentally friend alternatives to the synthetic polymers that are commonly used. PHAs are polyesters that produced and accumulated in intracellular granules by many microorganisms and can be produced by fermentation of renewable feed stocks, like oil palm biomass.

Bioplastics can be a healthy and sustainable material in lieu of traditional plastic as 100 percent degradable, equally resistant and versatile. However, the chemical analysis of bio-plastic showed the presence of several chemical elements with large variability of mass fractions that indicates these plastics receive additives and may have been contaminated during manufacturing process and thereby has become potential environmental pollutants.

In Bangladesh, the plastic industry began its journey as a small industry in 1960. Then manufacture of plastic bags or packages was started in 1980. The average per capita plastics consumption is 5 kg per year in Bangladesh. A significant quantity of it is used food packaging. Still, PFPs are not widely used in Bangladesh. Therefore, the government should take proper steps to encourage industries to use organic source-derived food packages. Furthermore, stringent regulations should be formulated and regular monitoring of food packages and its additive contents ensured. n

The writer is a student of Microbiology at University of Chittagong.

Comments

Poll
Today's Question »
State minister for power Nasrul Hamid yesterday said everyone to have access to electricity by June. Do you think the feat achievable by the timeframe?
 Yes
 No
 No Comment
Yes 49.4%
No 46.6%
No Comment 4.1%
Most Viewed
Digital Edition
Archive
SunMonTueWedThuFri Sat
01
02030405060708
09101112131415
16171819202122
23242526272829
30

Copyright © All right reserved.

Editor : M. Shamsur Rahman

Published by the Editor on behalf of Independent Publications Limited at Media Printers, 446/H, Tejgaon I/A, Dhaka-1215.
Editorial, News & Commercial Offices : Beximco Media Complex, 149-150 Tejgaon I/A, Dhaka-1208, Bangladesh. GPO Box No. 934, Dhaka-1000.

Editor : M. Shamsur Rahman
Published by the Editor on behalf of Independent Publications Limited at Media Printers, 446/H, Tejgaon I/A, Dhaka-1215.
Editorial, News & Commercial Offices : Beximco Media Complex, 149-150 Tejgaon I/A, Dhaka-1208, Bangladesh. GPO Box No. 934, Dhaka-1000.

Disclaimer & Privacy Policy
....................................................
About Us
....................................................
Contact Us
....................................................
Advertisement
....................................................
Subscription

Powered by : Frog Hosting