Daltonganj: Five members of a family who died at Sikka village in Palamu district within eight days consumed adulterated mustard oil leading to epidemic dropsy, officials said on Friday.The deaths occurred between June 20 and 28. Three family members — Kuldip Mehta, 55, and daughters Babita, 20, and Indu, 18 — died in Palamu, while Savita Mehta, 24, and Nakul Mehta, 22, died during treatment at Rajendra Institute of Medical Sciences (Rims) in Ranchi.Palamu civil surgeon Dr Anil Kumar Srivastava got samples of the family’s mustard oil tested at the biochemistry laboratory of Medinirai Medical College and Hospital (MMCH), Daltonganj, on June 30. Four different tests detected the presence of argemone oil. To confirm the findings, the sample was sent to the State Food Testing Laboratory at Namkum, Ranchi.The laboratory’s report, signed by food analyst Chaturbhuj Meena on Thursday, also confirmed the presence of argemone oil.“Argemone oil is highly toxic. It leads to swelling of limbs and other severe symptoms or even organ damage or failure,” he added, asserting that the family suffered from epidemic dropsy, a condition associated with argemone poisoning.Anuj Mehta, 32, who lost his wife Savita, said there was a large growth of argemone weed around the family home. “I don’t know how it got mixed with the mustard oil. I am a driver and mostly stay out for work,” he said.District authorities have sought explanation from MMCH officials over an alleged 12-day delay in dispatching viscera samples of three victims. Show-cause notices were issued on Thursday to the MMCH medical superintendent and head of the forensic medicine and toxicology department, with 24 hours given to explain the delay. The replies are yet to be received, sources said.