MUMBAI: Forensic laboratories in Kalina have confirmed that rat poison present inside a watermelon caused the deaths of four members of the Dokadia family in Mumbai’s Bhendi Bazaar area.

Officials from the state forensic science laboratory (FSL) said traces of zinc phosphide, commonly used as rat poison, were detected in both the watermelon and the victims’ internal organs, including liver, kidney, spleen, stomach bile, and abdominal samples.

“There was no indication of external contamination on the fruit. The poison was inside the watermelon, and it is unlikely to have been injected,” a forensic official said.

The findings have now shifted the focus of the investigation toward how the toxic substance entered the fruit. JJ Marg police said the forensic report has been received and will be examined in detail before further action is taken.

Investigators are exploring multiple angles, including whether the poisoning occurred at the vendor’s end or if foul play was involved. Police are yet to determine whether the case was accidental, suicidal, or homicidal. Officials also stated that no rat poison was found inside the family’s home.

According to forensic experts, the case proved unusually difficult to crack and required 54 rounds of testing over 11 days before traces of the toxin were identified.

“The family had vomited out a large portion of the toxin, making detection extremely difficult,” an FSL official said.

Experts explained that ingestion of zinc phosphide produces phosphine gas inside the body, leading to a rapid drop in oxygen levels once it reaches the lungs.

“This is why the youngest child died first. The body’s ability to withstand the poison depends on factors like body mass and overall health,” the official added.

The deceased were identified as Abdullah Dokadia (44), his wife Nasreen (35), and their daughters Ayesha (16) and Zainab (12), residents of Mughal Building in Bhendi Bazaar’s Pydhonie area.

Police said the family had attended a late-night meal with relatives on April 26 and later ate watermelon at around 1.30 am. Only the four deceased consumed the fruit. Forensic tests on the chicken pulao and other food items served that night returned negative results.

Within hours, all four developed symptoms including vomiting, diarrhea, and severe discomfort before being rushed to hospitals, where they died one after another. Twelve-year-old Zainab died first around 10 am, while Abdullah succumbed later that night.

Former FSL director Dr Rukmani Krishnamurthy described zinc phosphide as highly toxic even in small quantities and said the poisoning could have been either intentional or accidental.

Doctors treating the family said survival chances reduce sharply if treatment is delayed. Dr Hemalata Arora of Nanavati Hospital explained that stomach washes are most effective within one hour of poison consumption.

“As four to five hours had passed before symptoms became severe, the quantity consumed was likely low. A higher dose would have caused much faster reactions,” she said.

Police also examined the family’s financial and medical background, including ayurvedic and unani medicines recovered from the house, though officials said there was no evidence so far suggesting family distress or conflict.