Rapid and simple determination of chloropropanols (3-MCPD and 1,3-DCP) in food products using isotope dilution GC–MS

The paper describes simultaneous determination of 3-monochloropropanediol (3-MCPD) and 1,3-dichloropropanol (1,3-DCP) in small specimens of food products. 3-MCPD and 1,3-DCP were isolated from soy sauce and other food products using alumina column extraction. Sample portions (1–2 g) spiked with deuterated 3-MCPD-d5 and 1,3-DCP-d5 as internal standards were mixed with 2 g of aluminum oxide and packed into small disposable column. The compounds were eluted with 25 ml dichloromethane, concentrated and derivatized with heptafluorobutyryl anhydride. GC–MS analysis was done in SIM mode. Four ion fragments were used for identification of 3-MCPD and 3-MCPD-d5, three ions were used for 1,3-DCP. The limit of detection was 1 ng/g, the limit of quantitation was 3 ng/g, the recovery was around 80%. Observed matrix effects were negligible for 3-MCPD and amounted to around 20% signal decrease for 3-DCP.