In the dry, sweltering fields of India’s state of Maharashtra, Sudhakar Tasgave sprays pesticides from dawn until dusk. Then, he lies awake.

“I barely sleep for four hours,” he says. The fatigue doesn’t fade overnight but rather accumulates. Each day begins with exhaustion and ends the same way.

Tasgave is 55, a farmworker in western India who’s spent more than two decades applying every chemical available in the region. He’s come to recognize a disturbing pattern. After a day of spraying, his nights become restless. “I kept wondering what was going wrong,” he recalls in an interview with science journalist Sanket Jain for Chemistry World.

Eventually, he began tracking his symptoms and realized he was not alone. When he told other farmers, many of them saw the same signs in themselves.

Across Yadrav village, sleeplessness was becoming as common as the pesticides coating their fields.

A Long Day, A Longer Night

The link between pesticide exposure and serious health consequences has been studied for decades. But a new line of research is exploring a more subtle, chronic toll: broken sleep.

In Thailand, a 2025 study of more than 27,000 farmers found that long-term pesticide exposure correlates strongly with sleep disorders. “Many groups of pesticides like organophosphates, carbamates and pyrethroids can interfere with neurotransmitters,” explains Chudchawal Juntarawijit, a toxicologist at Naresuan University and the study’s lead author. These chemicals disrupt the delicate balance of acetylcholine and GABA compounds that help slow down brain activity and signal the body that it’s time to rest.

The body’s sleep-wake cycle is partly regulated by melatonin. Some pesticides mimic its structure. Others interfere with its production. “Specific classes of pesticides may interfere with the melatonin pathways,” says Astrid Zamora, a postdoctoral epidemiologist at Stanford University. Her 2021 study found a connection between pesticide residues in the body and disrupted sleep in U.S. adults.

Zamora notes for Chemistry World that while human data is still limited, animal studies are more conclusive. One, focused on carbaryl (a widely used insecticide) showed that it suppresses melatonin production in the pineal gland, thereby shifting the body’s natural clock.

The overall result is trouble falling asleep. Trouble staying asleep. And trouble waking up with energy.

The Numbers Behind the Sleepless Farmers

Globally, pesticide use has nearly doubled since 1990. In 2022, it reached 3.7 million metric tons. That same year, the International Labour Organization estimated that 873 million agricultural workers are potentially exposed to these chemicals.

Field studies support what farmworkers have long suspected. In Uganda, researchers studied 253 small-scale farmers. Those who used pesticides more frequently reported significantly higher rates of insomnia, poor sleep quality, and loud snoring — all symptoms often linked to sleep apnea. Farmers who applied pesticides just three times per week were about four times more likely to snore.

In Spain, scientists in the Almeria region found that sleep disturbances among farmers stemmed from overactive nerve signals triggered by pesticide exposure. These chemicals interfered with enzymes like acetylcholinesterase, which help the nervous system reset. Without it, the brain stays on high alert.

Back in Thailand, Juntarawijit notes another physiological mechanism of pesticide exposure: inflammation. Long-term pesticide exposure, he says, inflames the brain and airways. “This contributes to sleep fragmentation and poorer sleep quality,” he adds.

Protective Measures, Often Ignored

Despite the risks, many farmers spray without gloves, goggles, or masks. Tasgave is one of them.

He sprays pesticides about 25 days a month, seven hours a day, earning just under £7 ($USD 9.5) a shift. “Sometimes the pesticides get into my eyes and nose and cause many problems, but I’ve gotten used to it,” he says. Some leave a stench that clings to the body for days. “No matter how much you bathe, the smell remains.”

Enduring the exposure has become a badge of honor. “If you can spray these pesticides, you’re considered strong,” he says.

But strength has limits. His sleep has all but disappeared. His health is deteriorating. And he doesn’t see a way out. “If I don’t spray pesticides, I won’t be able to make a living. If I do, I will die from their harmful effects.”

He is not being hyperbolic. In Jambhali, a nearby village, Dilip Shinde remembers a friend who died from acute pesticide poisoning. Another can no longer walk. “I’ve learned from other farmers’ experiences and stay extremely cautious,” Shinde says. He wears a mask. He washes frequently. He sprays less often. But even so, “Sometimes, I find it difficult to sleep, which affects my work the next day.”

Lessons from the Fields

There is growing scientific consensus that pesticides are interfering with sleep, but many gaps remain. For now, education and protective measures offer the most realistic path forward.

In Spain, researchers found that simply wearing gloves reduced the risk of insomnia by more than half. Masks also offered significant protection. But for that to matter, farmworkers must be made aware — and given the tools to act.

The challenge is stark. Many farmworkers, like Shinde, cannot read the labels on pesticide containers. Instructions are printed in English or regional languages they never learned. Without help, they rely on guesswork and traditions that equate toxic exposure with resilience and male bravado.

But that mindset is slowly changing.

One of the region’s elder farmers, Narayan Gaikwad, stopped using pesticides after a doctor diagnosed him with nail dystrophy and linked it to chemical exposure. His nails became brittle and pitted. He couldn’t sleep. He has since embraced organic farming and now teaches others to do the same.

The science is clear enough: pesticide exposure disrupts the body’s chemistry in ways that rob farmworkers of rest. But for many, sleep is just one more cost of doing business.

Every evening, Tasgave lies down and stares at the ceiling. Every morning, he wakes up — unrested, unresolved — and returns to the fields.

“Every day, I tell myself I’ll quit this work,” he says, “but that never happens.” His sprayer waits by the door.