Canadian Journal of Public Health

, Volume 108, Issue 3, pp e288–e295 | Cite as

Lifetime excess cancer risk due to carcinogens in food and beverages: Urban versus rural differences in Canada

  • Roslyn Cheasley
  • C. Peter Keller
  • Eleanor SettonEmail author
Quantitative Research


OBJECTIVES: To explore differences in urban versus rural lifetime excess risk of cancer from five specific contaminants found in food and beverages.

METHODS: Probable contaminant intake is estimated using Monte Carlo simulations of contaminant concentrations in combination with dietary patterns. Contaminant concentrations for arsenic, benzene, lead, polychlorinated biphenyls (PCBs) and tetrachloroethylene (PERC) were derived from government dietary studies. The dietary patterns of 34 944 Canadians from 10 provinces were available from Health Canada’s Canadian Community Health Survey, Cycle 2.2, Nutrition (2004). Associated lifetime excess cancer risk (LECR) was subsequently calculated from the results of the simulations.

RESULTS: In the calculation of LECR from food and beverages for the five selected substances, two (lead and PERC) were shown to have excess risk below 10 per million; whereas for the remaining three (arsenic, benzene and PCBs), it was shown that at least 50% of the population were above 10 per million excess cancers. Arsenic residues, ingested via rice and rice cereal, registered the greatest disparity between urban and rural intake, with LECR per million levels well above 1000 per million at the upper bound. The majority of PCBs ingestion comes from meat, with values slightly higher for urban populations and LECR per million estimates between 50 and 400. Drinking water is the primary contributor of benzene intake in both urban and rural populations, with LECR per million estimates of 35 extra cancers in the top 1% of sampled population.

CONCLUSION: Overall, there are few disparities between urban and rural lifetime excess cancer risk from contaminants found in food and beverages. Estimates could be improved with more complete Canadian dietary intake and concentration data in support of detailed exposure assessments in estimating LECR.

Key Words

Risk assessment diet carcinogens urban health rural health 


OBJECTIFS: Explorer les écarts dans le risque excédentaire à vie de cancer en zone urbaine et en zone rurale associé à cinq contaminants précis trouvés dans les aliments et les boissons.

MÉTHODE: Nous avons estimé l’absorption probable des contaminants à l’aide de simulations de Monte-Carlo portant sur les concentrations de contaminants combinées aux habitudes alimentaires. Les concentrations d’arsenic, de benzène, de plomb, de biphényles polychlorés (BPC) et de tétrachloréthylène (PERC) ont été dérivées d’études gouvernementales d’exposition par voie alimentaire. Les habitudes alimentaires de 34 944 Canadiens dans 10 provinces provenaient du cycle 2.2, Nutrition, de l’Enquête sur la santé dans les collectivités canadiennes de Santé Canada (2004). À partir des résultats des simulations, nous avons calculé le risque excédentaire à vie de cancer (REAVC) associé.

RÉSULTATS: Lorsque nous avons calculé le REAVC associé aux aliments et aux boissons pour les cinq substances choisies, nous avons obtenu un risque excédentaire inférieur à 10 par million pour deux substances (le plomb et le PERC); pour les trois autres substances (l’arsenic, le benzène et les BPC), au moins 50 % de la population était au-dessus du seuil de 10 cancers excédentaires par million. Les résidus d’arsenic, ingérés dans le riz et les céréales de riz, ont présenté la plus grande disparité entre les niveaux d’absorption en zone urbaine et rurale, avec un REAVC par million très au-dessus de 1 000 par million à la limite supérieure. La majorité des BPC ingérés le sont dans la viande, avec des valeurs légèrement supérieures dans les populations urbaines et un REAVC qui se situerait entre 50 et 400 par million. L’eau potable est la principale source d’absorption du benzène, tant dans les populations urbaines que rurales, avec un REAVC par million estimé à 35 cancers excédentaires dans le centile supérieur de la population échantillonnée.

CONCLUSION: Dans l’ensemble, il y a peu de disparités entre les zones urbaines et rurales pour ce qui est du risque excédentaire à vie de cancer associé aux contaminants trouvés dans les aliments et les boissons. Les estimations du REAVC pourraient être améliorées si l’on disposait de données plus complètes sur les apports alimentaires et les concentrations au Canada pour appuyer les évaluations approfondies de l’exposition.

Mots Clés

évaluation des risques régime alimentaire cancérogènes santé en zone urbaine santé en zone rurale 


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Copyright information

© The Canadian Public Health Association 2017

Authors and Affiliations

  • Roslyn Cheasley
    • 1
  • C. Peter Keller
    • 1
  • Eleanor Setton
    • 1
    Email author
  1. 1.Department of GeographyUniversity of VictoriaVictoriaCanada

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