INFANTS AND YOUNG CHILDREN
For physiological and behavioral reasons, children are at a higher risk than adults for both exposure to environmental toxicants and for adverse health effects from those toxicants (Canha et al. 2016).
Infants are exposed to high concentrations of volatile organic compounds (VOCs) that are emitted from crib mattresses and crib mattress covers (Boor et al. 2014).
Another reason that children are more vulnerable to the adverse effects of air pollution than adults is that 80% of alveoliare formed postnatally, and changes in the lung continue through adolescence (Dietert et al. 2000). During the early postneonatal period, developing lungs are highly susceptible to pollutants.
Children have immature immune, pulmonary, and nervous systems that may be significantly affected by environmental toxins, such as particulate matters, cleaning products, and pesticides chronically applied in residential use.
Children are more highly exposed to environmental pollutants than adults because they breathe more air per pound of body weight and chew or suck on toys and hands that have been in contact with pollutants (Klepeis et al. 2001).
Young infants breathe through their mouth and a number of older infants and young children continue to breathe more through their mouth than adults. A study by the American College of Medical Toxicology states that this difference in breathing through their mouth may increase children’s risk of pulmonary exposure to respirable particulates which, for an adult breathing through the nose, may get filtered through the upper respiratory airway (Flynnetal.2000).
Babies crawl on the floor and young children walk, run, and play on the floor; thus, the breathing zone of the children is much lower (up to 1 m from the floor). This zone will be referred to as the child breathing zone (CBZ).
Resuspension of respirable particulates is caused by walking-induced turbulence in a room, and shorter people are exposed to more resuspended particulates than taller people.
Many household products for cleaning and maintenance such as disinfectants and pesticides contain and release PM 2.5 and numerous VOCs more or less that lead to long-term health concerns such as child developmental and hormonal issues. (Corsell et al., Hodgson et al.)
Research by Tripathii, Laquatra shows that IAQ can be significantly worse in the CBZ than in the adult breathing zone (ABZ).
Research by Tripathii, Laquatra shows that the assumption of uniform pollutant concentration in indoor environments can be an erroneous assumption of breathing concentration risk.
Although there is an increasing awareness that children are vulnerable to poor IAQ, in the scientific community there is very limited research with a focus on IAQ in the CBZ. There is no current IAQ management system that specifically focuses on improving IAQ in the CBZ.
The negative impact of air pollutants starts before a child’s birth. Epidemiological studies have shown that children's exposure to air pollutants during fetal development and early postnatal life is associated with many types of health problems, including abnormal development, low birth weight (LBW), very low birth weight (VLBW), preterm birth (PTB), intrauterine growth restriction (IUGR), congenital defects, decreased lung growth, increased rates of respiratory tract infections, childhood asthma, behavioral problems, neurocognitive defects, and infant mortality,(Levy et al. 2000; Samet et al. 2000; Chay and Greenstone 2003; Currie and Neidell 2005; Arceo, Hanna, Oliva 2012).
A study conducted on expectant mothers in Los Angeles, observed that poor ventilation resulting in poor indoor air quality leads to higher rate of preterm birth and low birth weight of babies.1
A study published in the American Journal of Public Health in 2001 “found elevated risks for childhood ALL (Acute Lymphoblastic Leukemia) associated with substantial postnatal exposure to some household activities and pre-birth and postnatal exposure to indoor house painting, especially if more than 4 rooms in the house had been painted while the mothers were pregnant.” (Freedman et al). These increase the Volatile Organic Compounds (VOC) concentrations in IAQ. Some VOCs like benzene, and formaldehyde, are known carcinogens (EPA). The severity of the reaction to VOCs will depend on the chemical itself. Exposure to VOCs during pregnancy have the potential depending on dose and timing of exposure to cause a variety of neurobehavioral disorders including attention deficits, reduced IQ, learning and memory deficiencies 2 (Freedman et al).
A recent study by Stanford University shows that pregnant women who breathed air pollutants, especially carbon monoxide, were nearly twice as likely to have babies with birth defects. A study on expectant mothers in Los Angeles observed that poor ventilation resulting in poor indoor air quality leads to higher rates of preterm birth and low birth weights of babies (Flynn et al. 2000). Pollutant levels spike with everyday cooking, use of a wood-burning fireplace, smoking, cleaning chemicals, and air fresheners (Ritz et al. 2007). Furthermore, the risk is more pronounced for low-income families (Laquatra et al. 2005).
Limited-resource households have been shown to face a disproportionate exposure to indoor air pollutants and are at a disadvantage to address the issue because of the costs associated with pollutant testing and mitigation (Laquatra et al. 2005).
While outdoor air quality is largely beyond an individual’s control, indoor air quality is more within an individual’s control.
- [1](Source: Ritz, B.; Wilhelm, M.; Hoggatt, K.J.; Ghosh, J.K. (2007). Ambient air pollution and preterm birth in the environment and pregnancy outcomes study at the University of California, Los Angeles. American Journal of Epidemiology 166(9): 1045-1052.)
- [2](Source: Freedman DM, Stewart P, Kleinerman RA, Wacholder S, Hatch EE, Tarone RE, et al. (2001). Household solvent exposures and childhood acute lymphoblastic leukemia. American Journal of Public Health. 91(4), 564-7)