House cleaning with chlorine bleach and the risks of allergic and respiratory diseases in children

Abstract

Chlorine bleach or sodium hypochlorite can inactivate common indoor allergens. In this cross-sectional study we evaluated to what extent regular house cleaning with bleach can influence the risks of respiratory and allergic diseases in children. We studied a group of 234 schoolchildren aged 10-13 yr among whom 78 children were living in a house cleaned with bleach at least once per week. Children examination included a questionnaire, an exercise-induced bronchoconstriction test and the measurement of exhaled nitric oxide (NO) and of serum total and aeroallergen-specific immunoglobulin (Ig)E, Clara cell protein (CC16) and surfactant-associated protein D (SP-D). Children living in a house regularly cleaned with bleach were less likely to have asthma (OR, 0.10; CI, 0.02-0.51), eczema (OR, 0.22; CI, 0.06-0.79) and of being sensitized to indoor aeroallergens (OR, 0.53; CI, 0.27-1.02), especially house dust mite (OR, 0.43; CI, 0.19-0.99). These protective effects were independent of gender, ethnicity, previous respiratory infections, total serum IgE level and of family history of allergic diseases. They were however abolished by parental smoking, which also interacted with the use of bleach to increase the risk of recurrent bronchitis (OR, 2.03; CI, 1.12-3.66). House cleaning with bleach had effect neither on the sensitization to pollen allergens, nor on the levels of exhaled NO and of serum CC16 and SP-D. House cleaning with chlorine bleach appears to protect children from the risks of asthma and of sensitization to indoor allergens while increasing the risk of recurrent bronchitis through apparently an interaction with parental smoking. As chlorine bleach is one of the most effective cleaning agent to be found, these observations argue against the idea conveyed by the hygiene hypothesis that cleanliness per se increases the risk of asthma and allergy.

Outdoor swimming pools and the risks of asthma and allergies during adolescence

“…This is consistent with earlier studies showing that the associations between passive smoking and asthma risks are the strongest during early childhood and then disappear with increasing age [24]. Interestingly, the present study confirms that house cleaning with bleach protects against the risk of asthma, probably by decreasing the exposure to indoor allergens and harmful microbial agents, such as fungal products or endotoxins [25,26]. This protection afforded by bleach is not inconsistent with the increased asthma risks associated with swimming pools, since children living in a house cleaned with bleach are not directly in contact with chlorination products as they are when playing or swimming in an chlorinated pool [25].…”

National income, self-reported wheezing and asthma diagnosis from the World Health Survey

“…In most of the countries identified in the middle-national income group, GINA reports have identified very high-mortality rates due to asthma relative to the low prevalence reported for this group [13,16,17]. However, even with low country reporting rates, other influential factors may be at play, such as: environmental (urban air) pollution, which has been identified as a risk factor for respiratory illness in both children [31][32][33][34] and adults [17,35]; access to healthcare and disease information (which allow for disease identification, treatment, and management) [17,[36][37][38]; and the highly contested hygiene hypothesis [39][40][41][42][43][44], which postulates that a lack of exposure to dirt in childhood may increase an individual's susceptibly to respiratory illnesses, asthma in particular, and may explain the high asthma prevalence observed for the high-income countries [1,2,13,17,34,40], although high urbanisation is more likely to be the driving factor. Among low-income countries, the influencing factors may be exacerbated by poorer access to healthcare.…”

Respiratory allergy caused by house dust mites: What do we really know?

“…Domestic cleaning offers a cost-effective universal approach, and evidence that HDM populations are reduced by cleaning is longstanding in the literature. An early study found 1.4 times more HDM allergen in beds where the housekeeping was poor, 39 whereas using chlorine bleach, 40 maintaining good ventilation, 37 and washing textiles regularly with a detergent at higher temperatures 41 appear to remove most HDMs. Focusing on the bed area as a target for allergen reduction, the use of mite-impermeable mattress covers, 14,42 daily vacuuming of mattresses, 43,44 and choice of a more powerful model of vacuum cleaner 38,45 have been shown to reduce HDM concentrations.…”