By Dotun Ibiwoye,
Imagine the aftermath of consuming tiny bits of plastics daily and you are still healthy for an entire lifetime of a man?
Microplastics are present in 90 percent of table salts tested worldwide, a study published earlier this month found.
Researchers analyzed 39 brands of sea, rock and lake salt produced in 16 different countries on six continents and determined microplastics were in 36 of them, according to the study published in Environmental Science and Technology.
Despite the fact that marine plastic pollution has been studied for decades, the magnitude and effects of plastic pollution is only just beginning to be explored.
Scientists have found microplastics in the soil, tap water, bottled water, beer and even in the air we breathe, in the past few years, and there’s growing concern about the impending health risks they pose to humans beings.
There are no accurate figures on the extent of the problems of microplastics, because the research on it on land and in freshwater is still in its infancy, but some studies have suggested there are more microplastics on land than there are in our oceans.
Seung-Kyu Kim, a marine science professor and author of the study made this month, said in a statement: “”In order to limit our exposure to microplastics, preventative measures are required, such as controlling the environmental discharge of mismanaged plastics and more importantly, reducing plastic waste.
The three brands that did not contain microplastics are a refined sea salt from Taiwan, a refined rock salt from China and an unrefined sea salt produced through solar evaporation from France, National Geographic reported.
The density of microplastics found varied by brand, with many of the salt samples from Asian countries testing higher, National Geographic reported.
The study, led by South Korea and Greenpeace, determined salt from Indonesia, which has some of the worst levels of plastic pollution in the world, tested highest for microplastic contamination, National Geographic reported.
Here to stay
By 2050, the global plastic production is expected to triple. Unfortunately, some plastics can take hundreds of years to dissolve.
• Fragmented fibres – fibrous microplastics – are present in outdoor and indoor air.
• The inhalation of airborne fibrous microplastics is a question of size.
• Inhaled fibrous microplastics are likely to be biopersistent.
· There are more than 60 million metric tons of plastic fibers were produced in 2016.
• Airborne fibrous microplastics may also carry pollutants.
According to a report in the second quarter of this year, there are more than 330 million metric tons of plastics is produced each year, leaving potential sources of microplastic pollution all around us.
Source of the microplastics
The fertilizer is thought to be one of the paramount suppliers.
The semi-solid by-product of sewage water treatment — is used in many countries to fertilize plants. But the part of the sewage can contain microplastics in the form of microbeads found in cosmetics that have been washed down clothing fibers and sink and get flushed into sewage systems after synthetic clothes are machine washed.
Exactly what happens to these plastics once they’re in the environment is largely unknown.
Though there’s little known about the effect on plants or on the wider food chain, studies have shown that earthworms exposed to microplastics in soil have increased gut inflammation, slower growth and higher mortality.
Impacts on human health
Can airborne fibrous microplastics be breathable?
According to Science Directs’s journal on Environmental Science & Health, February 2018, ‘Microplastics in air: Are we breathing it in’?
The likelihood that airborne fibrous microplastics enter the respiratory system will be dependent upon size. First, it is important to discriminate between the terms inhalable and respirable. Particles and fibers able to enter the nose and mouth and deposit in the upper airway are inhalable, whilst those able to reach and deposit in the deep lung are respirable. Deposition in the airway is a function of aerodynamic diameter and within the respiratory zone, deposition falls off above 5 μm diameter.
The World Health Organisation defines a fiber as any particle that has a length >5 μm, with a diameter <3 μm and an aspect (length-to-diameter) ratio > 3:1.
Fibrous microplasticss that exceed these criteria may be inhaled, but are likely to be subjected to mucociliary clearance in the upper airways, leading to gastro-intestinal exposure.
Some fibrous microplastics may however avoid the mucociliary clearance mechanisms of the lung, especially in individuals with compromised clearance mechanisms.
Does microplastics accumulate in the human body?
The biopersistence of inhaled fibrous microplastics is related to durability in and clearance from the lung. In vitro tests have found plastic fibers to be extremely durable in physiological fluid: polypropylene, polyethylene and polycarbonate fibers showed almost no dissolution or changes to surface area and characteristics in a synthetic extracellular lung fluid after 180 days.
This suggests plastic fibers are durable and likely to persist in the lung .
Plastic fibers have been observed in pulmonary tissue, suggesting that the human airway is of a sufficient size for plastic fibers to penetrate the deep lung.
Historical analysis of lung biopsies from workers in the textile (polyamide, polyester, polyolefin, and acrylic) industry showed foreign-body-containing granulomatous lesions, postulated to be acrylic, polyester, and/or nylon dust.
These observations confirm that some fibers avoid clearance mechanisms and persist.
Occupational health risks
Interstitial lung disease is a work-related condition that induces coughing, breathlessness, and reduced lung capacity in workers processing either para-aramid, polyester, and/or nylon fibers.
Workers also present clinical symptoms similar to allergic alveolitis.
These health outcomes are indicative of the potential for microplastics to trigger localised biological responses, given their uptake and persistence.
