Signature tracing of PCBs congeners in breastmilk of mothers living in selected urban centers of Pakistan

Abstract

Polychlorinated biphenyls (PCBs) are banned toxic contaminants according to the Stockholm Convention of persistent pollutants (2001); however, they continue to be prevalent in the environment of Pakistan. The current study evaluates the risk to infants exposed to PCBs in breast milk from urban centers of Pakistan. The ∑14PCB concentrations ranged from ND to 118.36 ng/g lipid weight (l.w.) with a mean of 11.76. ± 4.88 ng/g l.w. These levels are greater than concentrations previously reported from Asia. The quantified PCB profile was also significantly (p < .05) related to the age of the mother while a negative correlation was observed with diet pattern (−0.26), fat content (−0.63), number of children (−0.185), and lactation (−0.19). There were significant differences among test locations with greater bioaccumulation observed in breast milk collected from urbanized Rawalpindi compared to less urbanized Jhang. The calculated estimated daily intakes of dioxin-like PCBs for infants were considerably higher than the recommended daily intake suggested by different organizations. The calculated hazard ratio (HR > 1) indicates health risks to infants in selected study regions.

Keywords:

• polychlorinated biphenyls
• human milk
• feeding infants risk
• urban centers
• Pakistan

Acknowledgments

The authors would like to acknowledge the efforts of the research staff at Nano Science Technology Institute, National Centre for Physics, Islamabad, Pakistan to provide and help us with the analytical facilities. The authors are gratified to the staff at environmental toxicology laboratory, College of Earth and Environmental Sciences, University of the Punjab, Pakistan and Sustainable Development Study Center, Government College University, Lahore, Pakistan. The authors also acknowledge the efforts of Abdul Rehman (Geophysics department, Quaid-e-azam University, Islamabad, Pakistan), having a supporting role in sample collection.

Authors contribution

Shagufta Tahir: Formal analysis, Investigation, Writing – original draft, Writing – review & editing; Abdul Qadir: Supervision, Review & editing, Project administration, Visualization. Conceptualization; Mehvish Mumtaz: Investigation, original draft, Writing – review & editing, Visualization, Conceptualization; Nadia Jamil: Visualization. Conceptualization; Mujtaba Baqar: Visualization, Conceptualization, Resources; Asad Ullah Saeed: Review & editing, Visualization; Naeem Khan: Methodology, Formal analysis, Resources; Richard Halbrook: Language editing and reviewing.

Data availability statement

The additional information is provided in the Supporting information (SI).

Declaration of interest

The authors declare no conflict of interest.

Ethical approval

The authors seek permission from bioethical committee, Department of Zoology, University of the Punjab, Lahore, Pakistan (Reference No: 1196-02) before starting sampling and experimental work.

Additional information

Funding

The authors would like to thank the College of Earth and Environmental sciences, University of the Punjab, Lahore, Pakistan for facilitating the research activities.