As supermarket chains in western nations make windfall profits, their aggressive pursuit of ever-lower wholesale prices is causing misery for people at the bottom end of the supply chain in Asia and elsewhere.

That's according to The Associated Press, which received an early copy of an NGO report that analyzed the top three shrimp producers in Vietnam, India and Indonesia. The three countries produce about half of the shrimp for the world's top four markets. 

It found a 20%-60% drop in earnings from pre-pandemic levels as producers struggle to meet pricing demands by cutting labor costs. 

In many places that's translated into unpaid and underpaid work through longer hours, wage insecurity as rates fluctuate, and many workers not even making the low minimum wages set in their countries. The report also found hazardous working conditions, particularly in India and parts of Indonesia, and even child labor in some regions of India.

"The supermarket procurement practices changed, and the working conditions were affected — directly and rapidly," Katrin Nakamura of Sustainability Incubator, who is identified as the lead author of the regional report, told AP. "Those two things go together because they're tied together through the pricing."

Supermarkets linked to facilities where exploited labor was reported by workers include Target, Walmart and Costco in the US; in the UK it was Sainsbury's and Tesco and Aldi and Co-op in Europe.

Germany's Aldi chain did not specifically address the issue of pricing, but said it uses independent certification schemes to ensure its products are responsibly sourced. 

Higher wholesale prices wouldn't necessarily mean higher prices for consumers and retailers, Sustainability Incubator said.

"Prices to farmers would be at least 200% higher than today if the shrimp sold in global north supermarkets was made at minimum wage rates and in compliance with applicable domestic laws for labor, workplace health, and safety," the report said. "This would not necessarily mean higher consumer prices, because supermarkets are already profiting at existing consumer prices."

The full 44-page report can be read here.