Using salt? You are taking a pinch of plastic

(Source: https://health.economictimes.indiatimes.com/news)

 

When you season your food with salt, chances are that you are sprinkling plastic on it — an infinitesimal bit of a bag, a cup, or cutlery. Researchers have found microplastics in table salt, a ubiquitous meal ingredient, thus suggesting that Gujarat’s addiction to single-use convenience is coming back to bite it.

Recently, three universities of Tamil Nadu along with the National Centre for Polar and Ocean Research, Goa, studied salt samples from Gujarat and Tamil Nadu. Both states are major producers of edible salt and depend on the sea to make it.

Microplastics are tiny particles, as minute as 100-200 micrometres, which shred away from single-use or general plastic items. These items include packaging material, cutlery, paints used for roads, polyester textiles, beads, fishing nets, tools, and cosmetics.

The total microplastic content ranged from 46-115 particles per 200g in Gujarat salt samples, according to the researchers. In Tamil Nadu’s case, it ranged from 23-101 particles per 200g. Since this is emerging research, no reference limits are available to work out the permissible levels.

The most common microplastics identified in edible salt were polyethylene, polyester, and polyvinyl chloride.

Assistant professor A Vidyasakar of the geology department of Tamil Nadu’s Periyar University said, “The sources of the microplastic fibers may be processing and packaging units of salt-producing companies.” Airborne particles could be another source, he said. According to Vidyasakar, 74.3% of the total microplastics found in the study were red-and-blue fibrous materials. “We want the states that produce and package salt to recognize microplastics as a problem,” Vidyasakar said. “We want the states to improve their refining processes.”

Another researcher, assistant professor S Krishna Kumar of the geology department of Tamil Nadu’s Malankara Catholic College, said, “Our team carried out a baseline study on the presence of the particles in Gujarat and Tamil Nadu samples.” Kumar added, “We are yet to investigate their effects on our bodies.” It will take a decade before the detrimental consequences are fully known, he said.

“But first we have to recognize presence of microplastics,” Kumar said. Other researchers were K Suresh Kumar, P Saravanan, and K Kasilingam of University of Madras; and K Neelavannan, S Anbalagan, and S Srinivasalu of the Institute for Ocean Management, Anna University. The research team also included S Kamaraj of the biotechnology department of Periyar University; and N S Magesh of the National Centre for Polar and Ocean Research.

Plastic in salt: Study calls for better processing

Ahmedabad: The revelation that microplastics lurk amid edible salt comes as an eye-opener for the state government and salt producers. The researchers who recorded the findings are calling for improved refining processes to reduce microplastics in salt.

Gujarat produces 76% of the country’s salt. Kharaghoda, Bhavnagar, Porbandar, and the Rann of Kutch are major salt-producing centres. The research study, published in Elsevier’s Marine Pollution Journal, has stated that of the solid microparticle pollutants separated from the samples, 90.3% were microplastic fractions and 9.7% were non-microplastic fractions. The study was carried out by a team of 10 scientists including geologists, ocean researchers, and biotechnologists

Polyethylene (78%) was the dominant microplastic pollutant, followed by polyester (19%). Polyvinyl chloride content was found too. “The packing material of salt was primarily composed of polyethylene. A few large-sized plastic fragments which were greater than 5mm were also observed in the samples,” the study said.

Approximately 16.2% and 15% of the microparticles that were analyzed in the crystal salt packets fall in the 500-1,000 micrometre and above 1mm size ranges. The 200-500 micrometre microplastic particles accounted for approximately 31.2% of the total particles, and 100-200 micrometre particles made up 37.7% of the total. “The common microplastic particles include fiber, pellet, and film,” the study said. The research involved Madras, Periyar, and Anna universities; Malankara Catholic College; and National Centre for Polar and Ocean Research.

“The [finding] of the study is that edible salt is dominated by fiber-shaped microplastic materials,” the researchers said. “The microplastics in salt were primarily made up of polyethylene materials.” The researchers went on to say: “The observed polyethylene in salt most probably came from processing and packing units of salt-producing industries, followed by airborne microplastic particles.”