News

Skin cream to shield farmers from pesticides

Manupriya

doi:10.1038/nindia.2018.139 Published online 30 October 2018

Praveen K. Vemula (centre) with co-researchers Ketan Thorat (left) and Sandeep Chandrashekharappa.

© Praveen K. Vemula

Indian scientists have come up with a skin cream that has the potential to protect farmers from the ill effects of pesticide exposure1.

Praveen Kumar Vemula, lead researcher of the study and a faculty member at the Institute for Stem Cell Biology and Regenerative Medicine (inStem) in Bengaluru, said the cream has so far been tested on rats only, where it has shown a promising 100 per cent protection against death from pesticide exposure. Human trials are due to begin within a year and half, he told Nature India.

Over-exposure to pesticides has been one of India’s long-standing farming problems. It has led to severe health issues and sometimes even death.

Pesticides, especially the ones that belong to the organophosphate category, are absorbed easily via the skin and nasal inhalation. Farmers are recommended use of physical barriers such as gloves, masks and boots to minimise physical exposure to pesticides. However, these measures are often too expensive and unsuitable for a tropical country like India.

The anti-pesticide products developed by the researchers.

© P. K. Vemula

In the past, researchers have even attempted to mitigate organophosphate toxicity with skin-based products (ointments) that create a barrier and do not allow the pesticide to penetrate through the skin. But these ointments have not been very successful.

In the new study, Vemula and co-researchers tried a different approach. Instead of creating a barrier on the skin, the proposed ointment works by degrading the organophosphates before it has had a chance to enter the body.

The main ingredient of the cream is a chemical called poly-oxime, chosen for two reasons: one, it works rapidly to deactivate the pesticide before it enters the skin, and two, it is robust enough to work in both tropical and cold climates.

Enthused by their success in rat-based studies, the researchers are now gearing up for human trials. “We have already developed human formulations, and detailed safety studies are being done. After their completion, we will initiate a pilot study in humans to demonstrate efficacy,” Vemula said.

Earlier, many studies have worked well in animal models. "But in controlled clinical trials2, 3, clear benefits could not be established," says Stevan Pecic, Assistant Professor of Chemistry and Biochemistry at California State University, Fullerton USA. Since their discovery in the mid-1950s a large body of research has focused on ways to improve existing oximes as a possible treatment for acute organophosphate toxicity, he points out. “It is hard to predict how poly-oximes will fare in human trials”, he says.

However, Vemula is confident about the technology. His team wants to commercialise products, such as the cream and a special range of protective suits and masks made up of an “active cloth”, through a startup company.

Since Indian farmers have poor purchasing power, he foresees some challenges in the commercialisation of these technologies and hopes the government can partner in distributing them.


References

1. Vemula, P. K. et al. Prevention of pesticide-induced neuronal dysfunction and mortality with nucleophilic poly-Oxime topical gel. Science Advances 17, 4 (2018) doi: 10.1126/sciadv.aau1780

2. Pawar, K. S. et al. Continuous pralidoxime infusion versus repeated bolus injection to treat organophosphorus pesticide poisoning: a randomised controlled trial. Lancet, 16, 2136-2141 (2006)  doi: 10.1016/S0140-6736(06)69862-0

3. Eddleston, M. et al. Pralidoxime in acute organophosphorus insecticide poisoning -- A randomised controlled trial. PLoS Med. 6, e1000104 (2009) doi: 10.1371/journal.pmed.1000104