Police investigating the deaths of three members of the same family say a power cut could be to blame.
Zeli dos Anjos, 61, prepared the traditional ‘Bolo de Natal’ cake on December 23 in the southern Brazilian city of Torres.
But she was among six family members who were hospitalised with food poisoning shortly after eating the cake – and three of her relatives have since died.
Maida, 58, Neuza, 65, and Neuza’s daughter Tatiana, 43, died in hospital, with traces of arsenic found in their bodies.
Torres-based police chief Marcos Vinicius Veloso said detectives were studying the possibility bacteria-ridden currants and other spoiled foods used as a cake topping after a power cut could be linked to the fatal poisonings.
Zeli, who has spoken briefly to police from her hospital bed, is said to have prepared the Christmas cake at her holiday home in the beach resort of Arroio do Sal.
She had not visited for a while because she had been living at her main home in Canoas, police said.
The family ate the suspect cake in an apartment in Torres where Maida lived with her husband.
Mr Veloso said: ‘Zeli had spent some time away from her place in Arroio do Sal, and when she returned to it she found the fridge off because from the inquiries we’ve been able to make, it appears there’d been some sort of power cut there.
‘When she went into the property there was an unbearable smell.
‘Some of the things in the fridge, perishable foods like meat, were thrown away, but other items were re-used.
‘What we’re trying to confirm is that some of those items, like currants and other crystallised fruit, could have been used in the cake a month later.’
Following the Christmas horror it emerged Zeli’s husband had died from suspected food poisoning in September.
The death was not deemed suspicious at the time, but detectives have confirmed Paulo Luiz’s body will now be exhumed so a proper post mortem can take place.
Mr Veloso said earlier this week: ‘With the evidence we have collected, we do not know whether the poisoning was negligent or intentional.
‘So far, I have not been able to find any intentional conduct. However, other evidence that comes to light may contradict what I think now.
‘This is an investigation that requires great caution.’
Arsenic can be found in seafood, rice, mushrooms and poultry although many other foods including some fruit juices can also contain it.
Maida, a teacher, was the first to die. Her husband Jefferson, who also ate the cake, needed medical treatment but his symptoms were described as ‘minor’.
He told Brazilian media no-one in the family thinks Zeli had any intention of harming her relatives.
A 10-year-old child also ended up in hospital after eating the cake.
She is expected to be questioned again once she leaves hospital. Her current condition in hospital has been described as ‘stable’.
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