The Effect of Air Pollution in the Development of Acute Lymphoblastic Leukaemia - Literature review Example

The Effect of Air Pollution on the Development of Acute Lymphoblastic Leukaemia The Effect of Air Pollution inthe Development of Acute Lymphoblastic Leukaemia Belson et al (2010) cites air pollution as one of the risk factors of acute lymphoblastic leukaemia in children. Ionizing radiations are the pollutants that have the strongest association with lymphoblastic leukaemia. This study underscored the fact that many other environmental risk factors have a weak association with acute lymphoblastic leukaemia in children. Other environmental risk factors include non-ionizing radiations, hydrocarbons, and pesticides. Belson et al explained that childhood lymphoblastic leukaemia is a rare occurrence and this makes researchers to use retrospective case-control design. Steffen et al (2004) anticipated Belson et al’s finding about the weak link between exposure to hydrocarbons and acute lymphoblastic leukaemia among children. Their study investigated the impact of maternal occupational exposure to hydrocarbons when pregnant and leukaemia and found a weak link. According Steffen et al, residential traffic density has a significant association with child leukaemia. This manifested in the places where child leukaemia victims lived near a petrol station or a repair garage. The association suggested a causal association between exposure to benzene emitting sources and acute childhood lymphocytic leukaemia. Behren et al (2008) did not find a significant association between living in high traffic density areas and child acute lymphocytic leukaemia. They argued the resultant inconsistency between their findings on the topic and other studies’ findings could have been because of methodological differences. However, they brought in a plausible explanation to the inconsistency when they cited that different places and regions have varying traffic volumes and emission profiles. Traffic volumes and emission profiles of different places also vary with time and are therefore never stable. Behren et al also explained that the critical time for an environmental exposure to that is enough to cause the development of leukaemia in children is not known. Raaschou-Nielsen et al (2001) investigated the impact of exposure to traffic-related air pollution on the risk of developing childhood cancer. They concluded that traffic-related air pollution in residences does not cause leukaemia in children. This finding further supported the suppressed association between the two variables. However, these authors explained that their selection of cancer cases and control children from registries that were population-based could have been a source of bias in their study. They cited that there was a possibility of a differential misclassification of exposure that could have emanated from the oblivion of data providers about the selected children’s state of health. Ghosh et al (2013) investigated the impact of prenatal exposure to traffic-related air pollution and the associated risk of developing acute lymphoblastic leukaemia. They used a regression modelling and found that the two variables have a strong association. These researchers emphasized the role of air pollution by nitrogen oxides and nitric oxide especially in participants’ birthplace residence. This study established an increase in the odds of acute lymphoblastic leukaemia with slight increase in average nitrogen oxide, nitrogen dioxide, and nitric oxide levels. The findings of this study served to confirm a significant relationship between prenatal exposure to traffic exhaust and acute lymphoblastic leukaemia. Badaloni et al (2013) found no impact of air pollution on the incidence of acute lymphoblastic leukaemia. Theirs was a nationwide case-control study in Italy that tested the hypothesis that links traffic-related air pollution with paediatric leukaemia. They emphasized the impact of chronic exposure to a number of potential carcinogens. Pelissari et al (2009) explained that epidemiological studies on the impact of exposure to non-ionizing radiation on children susceptibility to lymphoblastic leukaemia are difficult to conduct. The retrospective approach adopted by many epidemiological studies makes it particularly hard to measure the exposure during the actual time that the harmful exposure occurs. Khalade et al (2010) asserted that exposure to benzene in the workplace increases susceptibility to leukaemia. However, their meta-analysis concluded that there is no association between benzene and chronic lymphoblastic leukaemia. Their study established a dose-response pattern in the impact of benzene in the workplace on the risk of leukaemia. The study provided quantitative estimates of the effect of this exposure and detected significant heterogeneity between different types of leukaemia. The specific estimate sizes of different types of leukaemia varied. The estimates values established in this study were significantly lower than those established in previous studies were. Riley (2000) investigated the risk that using pesticides has on children and found that it raises the risk of childhood cancers. Home and garden use of pesticides predisposes children to risks of inhaling thus developing acute lymphocytic leukaemia. These risks of childhood acute lymphocytic leukaemia are highest during nursing and pregnancy. Olsen (2006) stated childhood cancers are examples of diseases that have intrauterine aetiology and that can be identified using prenatal diethylstilbestrol (DES) exposure and vagina cancer in young mothers. This study demonstrates how the risk of developing acute lymphoblastic leukaemia compares with the impact of air pollution on the development of the disease. Buffler et al (2005) underscored that passive tobacco smoking is one of the risk factors of acute lymphoblastic leukaemia. The study stated that the findings on this element are varied. A case control study showed that parental smoking has a significant effect on acute lymphocytic leukaemia. The review alluded to two cohort studies that reported that there was no association between maternal prenatal smoking and children’s susceptibility to childhood leukaemia. Buffler et al explained that these disparities could be because of misclassification and bias. Bias resulted from failure to adjust to possible cofounders including race, diet, random digital controls and hospital controls. Buffler et al called on future research studies on parental smoking to address these limitations. Conclusion Literature on the effect of air pollution on the development of acute lymphoblastic leukaemia (ALL) shows varying findings on the existence and strength of association between different air pollutants and the disease. There is imminent consensus among this cited literature as to the strong association between ionizing radiations and the development of acute lymphoblastic leukaemia. Some researchers have a found a link between chronic exposure to traffic emissions and the prevalence of ALL especially in densely populated areas. Some have asserted that there is no link between the two. Pesticides and hydrocarbons have a causal link with ALL. There is a need for more research into the existence and strength of association between different environmental risk factors and ALL. Reference List Badaloni, C., Ranucci, A., Cesaroni, G., Zanini, G., Vienneau, D., Al-Aidrous, F., De Hoogh, K., Magnani, C., Forastiere, F. SETIL Study Group. 2013. Air pollution and childhood leukaemia: a nationwide case-control study in Italy. Occup Environ Med. 70(12):876-83. Behren, Julie Von, Reynolds, Peggy, Gunier, Robert B., Rull, Rudolph P., Hertz, Andrew, Urayama, Kevin Y., Kronish, Daniel, Buffler, Patricia A. 2008. Residential Traffic Density and Childhood Leukaemia Risk. Cancer Epidemiol Biomarkers Prev.17: 2289. Belson, Martin, Kingsley, Beverley & Holmes, Adrianne. 2010. Risk Factors for Acute Leukaemia in children: A Review. Environmental Health Perspectives. 118(90). A380. Buffler, Patricia A., Kwan, Marilyn L., Reynolds, Peggy & Urayama, Kevin Y. 2005. Environmental and Genetic Risk Factors for Childhood Leukaemia: Appraising the Evidence. Cancer Investigation, 1: 60 – 75. Ghosh, Jo Kay C., Heck, Julia E., Cockburn, Myles, Su, Jason, Jerrett, Michael & Ritz Beate. 2013. Prenatal Exposure To Traffic-related Air Pollution and Risk of Early Childhood Cancers. Am. J. Epidiol. 178(8). 1233 – 1239. Khalade, Abdul, Jaakkola, Maritta S, Pukkala, Eero & Jaakkola, Jouni J.K. 2010. Exposure to benzene at work and the risk of leukaemia: a systematic review and meta-analysis. Environmental Health. 9:31  Olsen, Jorn. 2006. How to study cancers with a possible intrauterine etiology. Eur J Endocrinol 155 S59 – S64. Pelissari, Daniele Maria, Barbieri Flavio Eitor & FilhoVictor Wunsch. 2009. Magnetic Fields and Acute Lymphoblastic Leukaemia in Children: a Systematic review of case-control studies. Cad. Saude Publica, Rio de Janeiro, 25 Sup 3: S441 – S452. Raaschou-Nielsen, Ole, Hertel, Ole, Thomsen, Birthe L., Olsen, Jorgen H. 2001. Air Pollution from Traffic at the Residence of Children with Cancer. Am. J. Epidemiol. 153(5): 433 – 443. Riley, Beckey. 2000. The Risks that Pesticides Pose to Children. Northwest Coalition for Alternatives to Pesticides. Steffen, C., Auclerc, M.F., Auvrignon, A., Baruchel, A., Kebaili, A., Lambilliotte, A., Leverger, G., Sommelet, D., Vilmer, E., Hemon, D., Clavel, J. 2004. Acute childhood leukaemia and environmental exposure to potential sources of benzene and other hydrocarbons; a case-control study. Occup Environ Med. 61: 773 – 778. Read More