Abstract Human exposure to environmental hazards is a major public health problem along the US-Mexico border due to socio-economic, cultural and political factors. Childhood lead exposure is endemic in areas of extreme poverty and substandard housing. Hispanic children of indigent, poorly-educated, disenfranchised families are at disproportionate risk. Risk management is contingent upon consideration of the interrelationships between socioeconomics, politics, and culture. This case study explains childhood lead poisoning in a colonia family living at subsistence level from such a perspective. The purpose of the study was to identify, explain, and ameliorate lead exposure pathways. Case study methodology was used to support or refute the proposition that these children were exposed to occupational lead. The children were the study sampling unit and the family a subunit. An embedded single case explanatory design was appropriate. Data were collected from exposure surveys, environmental and blood specimens, and review of medical records. Pattern-matching and explanation-building techniques were used to analyze data. The study illustrated how extreme poverty, lack of access to health services, social isolation, language and legal barriers, and hazardous occupations may be singularly common risk factors for Hispanic children on the US-Maxico border. The study is pertinent to public health nurses who work with this population.