Electronic Thesis and Dissertation Repository

Thesis Format



Master of Arts




Waters-Rist, Andrea.


A plethora of changes occurred in nineteenth century Montreal including industrialization, population growth, urbanization, and women in the workforce. These changes likely affected how infants and children were cared for, including breastfeeding and weaning practices. Using stable carbon and nitrogen isotope analysis of serial dentine sections of 21 teeth from a French-Canadian population interred at Saint Antoine (AD 1799-1854), this study reconstructs infant feeding practices from a low-middle socioeconomic status population. Adult female diet emphasized C3 foods with variable terrestrial and aquatic protein. Lack of isotope results limited information about the diets of subadults. In one individual, weaning was underway by 1.0 and completed before 2.5 years-of-age. The cause of the poor isotope results has not been identified but could include diagenesis or laboratory procedures. This study demonstrates the importance of limiting sample destruction, as by only using half the tooth the remaining portion is available for future analysis.

Summary for Lay Audience

During the nineteenth century, Montreal experienced pronounced change due to industrialization and urbanization. These changes caused population growth, increased immigration, urban expansion, and women, typically of lower socioeconomic status, to enter the paid workforce. These changes exacerbated already existing health and sanitation problems and contributed to an increase in infant and child sickness and death, leading Montreal to be regarded as one of the deadliest North American cities. These changes likely also affected how infants and children were cared for, including breastfeeding and weaning practices and raises questions about if infants were still breastfed, and, if so, was it for a shorter period? What weaning foods were given and were they safe or contaminated? Breastfeeding and weaning can be investigated using teeth, which begin forming in the womb and finish in our teens. Tooth dentine is formed in incremental layers that are laid down at a known age. These layers do not change after formation thereby preserving a record of a person’s life during tooth formation. Using a chemical method that looks at different forms of carbon and nitrogen (called isotopes) in the dentine layers, researchers can tell if a baby was breastfed, for how long, when weaning began, and what weaning foods were used.

This study uses carbon and nitrogen isotopes of dentine sections from subadults (years) who were interred at the Saint Antoine cemetery (AD 1799-1854) in Montreal to determine the breastfeeding and weaning practices of a low to middle socioeconomic group. The mothers consumed a diet of mixed plant sources, as well as a variety of animal proteins and fish. Unfortunately, most of the subadults’ results were unusable but one individual demonstrated that the weaning process was completed between 1 and 2.5 years, and that weaning foods were made from wheat, rye, barley, or oats. The cause of the poor results for the remaining subadults could not be concluded, but may include changes from the burial environment, contamination, or laboratory procedures. This study highlights the importance of limiting sample destruction, and the half tooth retained could be used for future study.

Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

Dental Scoring.xlsx (174 kB)
Dental scoring for all subadults, recorded in Microsoft Excel.

thesischangereport.docx (70 kB)