Abstract
Environmental risk factors associated with malignancy of pediatric neuroblastic tumours are not well-known and few studies have examined the relationship between industrial emissions and neuroblastic tumour diagnosis. A retrospective case series of 310 patients was evaluated at a tertiary hospital in Toronto, Canada between January 2008, and December 2018. Data from the National Pollutant Release Inventory (NPRI) were used to estimate exposure for a dozen chemicals with known or suspected carcinogenicity or embryotoxicity. Comparative analysis and predictive logistic regression models for malignant versus benign neuroblastic tumours included variables for residential proximity, number, and type of industries, mean total emissions within 2 km, and inverse distance weighted (IDW) quantity of chemical-specific industrial emissions estimated within 10 and 50 km of cases. No significant difference was seen between malignant and benign cases with respect to the mean nearest residential distance to industry, the number or type of industry, or the mean total quantity of industrial emissions within a 2 km radius of residential location of cases. However, there were statistically significant differences in the interpolated IDW emissions of dioxins and furans released between 1993 and 2019 within 10 km. Concentrations were significantly higher in malignant neuroblastic tumours at 1.65 grams (g) toxic equivalent (TEQ) (SD 2.01 g TEQ) compared to benign neuroblastic tumours at 1.13 g TEQ (SD 0.84 g TEQ) (p = 0.05). Within 50 km 3 years prior to diagnosis, malignant cases were exposed to higher levels of aluminum, benzene, and nitrogen dioxide (p = 0.02, p = 0.04, and p = 0.02 respectively). Regression analysis of the IDW emissions within a 50 km radius revealed higher odds of exposure to benzene for malignant neuroblastic tumours (OR = 1.03, CI: 1.01–1.05, p = 0.01). These preliminary findings suggest a potential role of industrial emissions in the development of malignant pediatric neuroblastic tumours and underscore the need for further research to investigate these associations.
IUPAC nomenclature and chemical formulas list
Benzene: IUPAC name is “Benzene;” chemical formula is “C6H6”
Nitrogen Dioxide: IUPAC name is “Nitrogen Dioxide;” chemical formula is “NO2
Particulate Matter: “Particulate matter" is a general term that does not have an IUPAC name nor refer to any specific chemical compound with a single formula. Particulate matter can be composed of various materials, including carbon, organic chemicals, metals, and dust.
Aluminum: IUPAC name is “Aluminum;” chemical formula is “Al”
Lead: IUPAC name is “Lead;” chemical formula is “Pb”
Toluene: IUPAC name is “Methylbenzene;” chemical formula is “C7H8”
Styrene: IUPAC name is “Phenylethylene;” chemical formula is “C8H8”
Xylene: IUPAC name is “Dimethylbenzene;” chemical formula is “C8H10”
Arsenic: IUPAC name is “Arsenic;” chemical formula is “As”
Volatile Organic Compounds: "Volatile organic compounds" is a general term that does not have an IUPAC name nor refer to any specific chemical compound with a single formula. VOCs can be composed of various organic chemicals, such as benzene, toluene, ethylene, and propylene, among others.
Dioxins: "Dioxins" is a general term that refers to a group of chemical compounds with similar structures. The formula of individual dioxin compounds depends on the specific chemical structure.
Furans: "Furans" is a general term that refers to a group of chemical compounds with similar structures. The formula of individual furan compounds depends on the specific chemical structure.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Acknowledgements
This research was approved by the Hospital for Sick Children Research Ethics Board (no): 1000067979.