Solid-state NMR reveals toxicological mechanisms of PCB Christian Totland Dept. of Chemistry, University of Bergen

PCB – the wonder chemical Polychlorinated biphenyls Non-flammable Very high chemical stability high boiling point (300-450°C) electrical insulating

PCB – the wonder chemical Transformers and capacitors Electrical equipment including voltage regulators, switches, re-closers, bushings, and electromagnets Oil used in motors and hydraulic systems Eelectrical devices or appliances containing PCB capacitors Fluorescent light ballasts Cable insulation Thermal insulation material including fiberglass, felt, foam, and cork Adhesives and tapes Oil-based paint Caulking Plastics Carbonless copy paper Floor finish Concrete additive

Why PCB now? Banned in Norway in 1980 Banned world wide in 2001

Why PCB now?

Toxicity – coplanar and non-coplanar PCB Dioxin Hormonal disorders Reduced immune response Cognitive and motoric birth defects Reduced cognitive development in children Etc… Cancer

POPC PCB 52 PCB 77 *The amount of PCB in the samples is above the limit where nonspecific toxicity occurs for noncoplanar PCB

31P NMR, lipid membranes: lineshapes Sheila Villasmil-Sánchez et al. 2013 Colloids Surf B, 105, 14-23

31P NMR, lipid membranes: CSA Michèle Auger, Université Laval Québec, Canada

Static, recorded Static, Simulated Magic angle spinning 50 % 18 % 32 %

Packing parameter: PCB 77 PCB 52

13C MAS NMR

Short summary Non-coplanar PCB induces higher bilayer fluidity Sufficient amounts of non-coplanar PCB in outer and inner lipid layer induce formation of channels - Both coplanar and non-coplanar PCB are positioned in the outer part of the bilayer core

Thank you for your attention! C. Totland, S. Steinkopf, W. Nerdal. Effects and Location of Coplanar and Noncoplanar PCB in a Lipid Bilayer: A Solid-State NMR Study Environmental Science and Technology, 2016, 50, 8290−8295