Packaging reducing benefit of vaccines to children
Food packaging chemicals can weaken the ability of vaccination jabs to protect young children, research suggests.
A study linked exposure in the womb or in the first years of life to lower immunity to tetanus and diphtheria.
The chemicals, known as perfluorinated compounds (PFCs), are widely used in manufacturing and food packaging.
Scientists analysed data on 587 children born in the Faroe Islands between 1999 and 2001.
The children were tested for immune responses to tetanus and diphtheria vaccinations at the ages of five and seven years.
Researchers also measured PFC levels in the blood of mothers and five-year-olds.
The findings, published yesterday in the Journal of the American Medical Association, showed that PFC exposure was associated with fewer numbers of antibodies. It also increased the chances of children having antibody levels insufficient to provide long-term protection.
Doubling the concentrations of three major PFCs led to a halving of antibody levels in children at age seven.
Study leader Dr Philippe Grandjean, from the Harvard School of Public Health in Boston, US, said: "Routine childhood immunisations are a mainstay of modern disease prevention.
"The negative impact on childhood vaccinations from PFCs should be viewed as a potential threat to public health."
Exposure to two common PFCs before birth had a negative impact on diphtheria vaccinations.
A two-fold increase in levels of one, perfluorooctane sulfonic acid (PFOS), reduced antibody counts by 39% in five-year-olds.
"If the associations are causal, the clinical importance of our findings is therefore that PFC exposure may increase a child's risk for not being protected against diphtheria and tetanus, despite a full schedule of vaccinations," the authors wrote.
The trend may reflect a more general impact on the immune system's ability to fight infection, said the scientists.
"PFC-associated decreases in antibody concentrations may indicate the potential existence of immune system deficits beyond the protection against the two specific bacteria examined in this study," they added.
The fishing community of the Faroe Islands, which lie between Scotland and Iceland, was chosen for the study because frequent consumption of marine food is associated with increased PFC exposure.
Meanwhile, a separate study published yesterday challenged the belief that frying food in olive or sunflower oil increases the risk of heart disease or early death.
The study goes against the idea that frying food is generally bad for the heart but experts said this "does not mean that frequent meals of fish and chips will have no health consequences."
A team drawn from research centres, universities and hospitals in Spain analysed data from almost 41,000 adults aged 29 to 69 who did not have heart disease at the start of the study.
They were divided into four groups according to how much they ate foods fried in olive oil or sunflower oil, from the lowest to highest amounts.
People were asked about food consumed in a typical week during the previous 12 months, with foods consumed at least twice a month recorded.
Fried foods included those that were deep fried or pan fried and could be battered, crumbed or sauteed.
During an 11-year follow-up, there were just over 600 "coronary heart disease events", such as heart attacks, and just over 1,100 people died from any cause.
Analysis showed no differences between the four groups of people in the risk of heart disease or dying. The results also did not vary between those who used olive oil for frying and those who used sunflower oil.
Writing online in the British Medical Journal (BMJ), the experts said: "In a Mediterranean country where olive and sunflower oils are the most commonly used fats for frying, and where large amounts of fried foods are consumed both at and away from home, no association was observed between fried food consumption and the risk of coronary heart disease or death."
- John von Radowitz in Washington
Irish Independent
