Scimex: A European study has found that exposure to bleach, through its use as a cleaning product in the home, is linked to higher rates of childhood respiratory problems and other infections. The researchers report that when bleach was used for cleaning at home at least once a week, it correlated with an increased risk of flu, tonsillitis and any other recurrent infections for the children who lived in those households.
Although modest, the results are of public health concern in light of
the widespread use of bleach in the home, say the researchers, who call
for further more detailed studies in this area.
The researchers looked at the potential impact of exposure to bleach in
the home among more than 9000 children between the ages of 6 and 12
attending 19 schools in Utrecht, The Netherlands; 17 schools in Eastern
and Central Finland; and 18 schools in Barcelona, Spain.
Their parents were asked to complete a questionnaire on the number
and frequency of flu; tonsillitis; sinusitis; bronchitis; otitis; and
pneumonia infections their children had had in the preceding 12 months.
And they were asked if they used bleach to clean their homes at least
once a week.
Use of bleach was common in Spain (72% of respondents) and rare (7%) in
Finland. And all Spanish schools were cleaned with bleach, while Finnish
schools were not.
After taking account of influential factors, such as passive smoking at
home, parental education, the presence of household mould, and use of
bleach to clean school premises, the findings indicated that the number
and frequency of infections were higher among children whose parents
regularly used bleach to clean the home in all three countries.
These differences were statistically significant for flu, tonsillitis, and any infection.
The risk of one episode of flu in the previous year was 20% higher, and
recurrent tonsillitis 35% higher, among children whose parents used
bleach to clean the home.
Similarly, the risk of any recurrent infection was 18% higher among children whose parents regularly used cleaning bleach.
This is an observational study, so no definitive conclusions can be
drawn about cause and effect. Furthermore, the authors highlight several
caveats to their research.
For example, they didn't have any information on the use of other
cleaning products used in the home, and only basic information was
gathered on the use of bleach in the home, making it difficult to
differentiate between exposure levels.
But their findings back other studies indicating a link between cleaning
products and respiratory symptoms and inflammation, they say.
And they add: "The high frequency of use of disinfecting cleaning
products, caused by the erroneous belief, reinforced by advertising,
that our homes should be free of microbes, makes the modest effects
reported in our study of public health concern."
By way of an explanation for the associations they found, they suggest
that the irritant properties of volatile or airborne compounds generated
during the cleaning process may damage the lining of lung cells,
sparking inflammation and making it easier for infections to take hold.
Bleach may also potentially suppress the immune system, they say.