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Chloropropanols such as 3-monochloropropane-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) have drawn increasing attention due to their release from food contact paper and their potential carcinogenic effects. In this study, the effects were investigated of water extraction conditions on release of chloropropanols from food contact paper, and the extraction efficiencies of chloropropanols by water extract and migration method were compared. Cold water was found to be more severe than hot water for extraction of chloropropanols, with the highest water extraction value obtained at 23°C. Two hours of extraction was sufficient as the chloropropanols can be fully extracted from food contact paper within a short period of time. Increase of temperature in the range of 10°C-60°C had little impact on release of chloropropanols, however, the extraction of chloropropanols decreased when high temperatures (80°C or above) were applied due to volatilisation losses. Hence, attention should be paid when choosing extract conditions representing the worst-case scenario. The water extraction value using EN 645 method gives higher results compared to migration test described in GB 31604.1 and GB 5009.156, suggesting that the water extract method was probably more severe. For migration test, aqueous-based simulants were found to be more conservative than oil-based simulants, suggesting the conventional experiment conditions applicable for compliance test of chloropropanols migration can be simplified and optimised.

Liquid–liquid equilibrium data for the ternary system of water + 1,3-dichloro-2-propanol + epichlorohydrin were determined at the temperature of (283.15, 293.15, 303.15) K and atmosphere pressure. The reliability of experimental method was examined by the mass balance verification and the Othmer–Tobias equation. The experimental data were successfully correlated with both the NRTL model and UNIQUAC model, and the NRTL model presents more satisfactory result. These LLE data and model parameters obtained in this work are helpful for understanding, designing, and developing epichlorohydrin synthesis processes.

Great attention has been paid to chloropropanols like 3-monochloro-1,2-propanediol and the related substance glycidol due to their presence in food and concerns about their toxic potential as carcinogens. The other chloropropanols 2-monochloro-1,3-propanediol, 1,3-dichloro-2-propanol and 2,3-dichloro-1-propanol have been found in certain foods, but occurrence data are generally limited for these compounds. 1,3-dichloro-2-propanol has the most toxicological relevance showing clear carcinogenic effects in rats possibly via a genotoxic mechanism. The dietary exposure to 1,3-dichloro-2-propanol is quite low. Calculated "Margins of Exposure" values are above 10,000. It is concluded that the 1,3-dichloro-2-propanol exposure is of low concern for human health. The toxicology of 2,3-dichloro-1-propanol has not been adequately investigated. Its toxicological potential regarding hepatotoxic effects seems to be lower than that of 1,3-dichloro-2-propanol. Limited data show that 2,3-dichloro-1-propanol occurs only in trace amounts in food, indicating that exposure to 2,3-dichloro-1-propanol seems to be also of low concern for human health. The dietary 2-monochloro-1,3-propanediol burden appears to be lower than that of 3-monochloro-1,2-propanediol. An adequate risk assessment for 2-monochloro-1,3-propanediol cannot be performed due to limited data on the toxicology and occurrence in food. This article reviews the relevant information about the toxicology, occurrence and dietary exposure to the chloropropanols 2-monochloro-1,3-propanediol, 1,3-dichloro-2-propanol and 2,3-dichloro-1-propanol.

1,3-Dichloro-2-propanol (DCP) is formed in foods under a variety of conditions. It was positive in a variety of in vitro genotoxicity tests, but was negative in two in vivo studies. DCP produced neoplasms at several sites in rats. Kidney tumours in male rats were selected as the critical tumour type. Dose-response modelling of the data for DCP gave a BMDL(10) for combined kidney carcinomas and adenomas in male rats of 9.62 mg/kg-body weight (bw)/day. The exposure of humans was estimated at an average of 0.00009 mg/kg-bw/day and a high exposure of 0.000136 mg/kg-bw/day. The MOEs for these exposures were 100,000 and 70,000, respectively.

1,3-dichoro-1,2-propanediol (1,3-DCP) is a contaminant of acid-hydrolyzed vegetable protein and a chlorinated compound used in the fabrication of industrial products such as hard resins, celluloid or paints. Several reports have suggested that chronic exposure to 1,3-DCP could produce neurotoxicity in vitro or in neurobehavioral aspects of experimental animals. The present study further explored the in vitro neurotoxic effects of 0.1-100 μM 1,3-DCP on PC12 and N18D3 cell lines. In addition, to investigate the effects of repeated ingestions of 1,3-DCP on neurobehavioral impairments parameters in rats, locomotor activity and landing foot splay tests were preformed, following the treatment of 1,3-DCP at doses of 10, 20, and 30 mg/kg/day for 11 weeks. We demonstrated that no significant neurotoxic effects in vitro and in neurobehavior were observed in the 1,3-DCP-treated rats compared to saline-treated control rats, whereas, acrylamide, used as a positive control, induced significant increases of all neurobehavioral deficit parameters in both male and female rats. On the other hand, body weight gain was significantly decreased in high dose 1,3-DCP-treated male rats as well as in acrylamide-treated rats. Taken together, these results suggest that 1,3-DCP does not produce in vitro neurotoxicity and the neuromotor deficits, at the dose levels of this study.

1,3-Dichloro-2-propanol (1,3-DCP) is a food born chloropropanol contaminant that has been detected during the production process of a wide range of foods. In this study, we investigated the effect of 1,3-DCP on lipid metabolism of mice after 13-week subchronic exposure. The data showed that 1,3-DCP (0.05–0.5 mg/kg/day) could induce nonalcoholic fatty liver disease (NAFLD) in C57BL/6J mice and the NOAEL was 0.01 mg/kg/day. In addition, we studied the signaling pathway to see how 1,3-DCP worked. The data showed that NAFLD induced by 1,3-DCP was due to the dysregulation of AMPK signaling pathway. As far as we are aware, this is the first study to use 13-week subchronic toxicology to investigate the effect of 1,3-DCP on the development of NAFLD in mice. Our study provided evidence for diet contaminants in the development of NAFLD and furthered the safety evaluation of 1,3-DCP through subchronic exposure.

Cyclization of 1, 3-dichloro-2-propanol with di(poly)-N-to-sylamides in the presence of sodium ethoxide in ethanol under reflux conditions gave hydroxyl-N-tosylcyclams in moderate yields. This procedure presents a practical and facile method for synthesis of [1+1] all-nitrogen cyclams.

Cyclization of 1, 3-dichloro-2-propanol with di(poly)-N-to-sylamides in the presence of sodium ethoxide in ethanol under reflux conditions gave hydroxyl-N-tosylcyclams in moderate yields. This procedure presents a practical and facile method for synthesis of [1+1] all-nitrogen cyclams.

Optimum conditions for the electrooxidation of 1,3-dichloro-2-propanol (1) to 1,3-dichloroacetone (2) by using a double redox system of Ru(VIII)/Ru(IV) and [Cl+]/Cl− are elucidated. The electrolysis of 1 in an AcOEt–aqueous NaCl (2:3 v/v) system buffered at pH 2–4 in a divided cell at 0–5°C gives 2 in 98% selectivity toward 1,1,3-trichloroacetone (3) under the current efficiency of 92%.

The influence of fasting (18 hours) on the hepatotoxicity of 1,3-dichloro-2-propanol (1,3-DCP) and on various hepatic parameters has been assessed in the rat. Fasting produced an enhancement of the hepatotoxicity which was associated with alterations in a variety of hepatic parameters when measured relative to protein content, most notably glutathione (GSH) levels (decrease) and CYP2E1-mediated enzyme activity (increase), two parameters previously identified as being important determinants to the toxicity. Fasting also decreased the liver weight normalized to body weight. When this was taken into account, total liver CYP2E1-mediated enzyme activity was not significantly altered whereas the total liver GSH level was markedly reduced following fasting. These results imply that the reduction in hepatic GSH is the principal determinant of the enhanced susceptibility to 1,3-DCP hepatotoxicity following fasting.

Optimum conditions for the electrooxidation of 1,3-dichloro-2-propanol (1) to 1,3-dichloroacetone (2) by using a double redox system of Ru(VIII)/Ru(IV) and [Cl+]/Cl− are elucidated. The electrolysis of 1 in an AcOEt–aqueous NaCl (2:3 v/v) system buffered at pH 2–4 in a divided cell at 0–5°C gives 2 in 98% selectivity toward 1,1,3-trichloroacetone (3) under the current efficiency of 92%.

With a view to studying the effect of bulky substituents in the cross-linking molecule on the physico-chemical properties of reacted cellulose, 1:3-dichloro-2-propanol and its acetyl, propionyl, and butyryl esters have been reacted with cellulose. Two cotton fabrics have been used: (i) a casement cloth of open structure and (ii) a poplin fabric of closed construction. The presence of cross-links and the retention of the ester groups in the cross-links have been established by the determination of the insolubility of the treated cellulose in cuprammonium hydroxide and the estimation of the ester contents. The effect of the substituent ester groups on the reactivity of these compounds and the resulting changes in the physico-chemical properties of the treated fabrics, such as dry and wet crease recovery, tensile strength, tear strength, stiffness as bending length, moisture regain, etc., have been assessed. It has been found that the cross-linking reactivity of these compounds decreases with the increase in molecular weight. Besides this, the ester group exerts a distinct influence on the various properties mentioned above. It is observed that the improved wet crease recovery, increased moisture regain, and stiffness of the fabrics treated with these compounds are inversely related to the increasing molecular weight of the substituent ester group. Similarly the losses in tensile and tear strength and the decrease in dry crease recovery become less as the molecular weight of the substituent ester group increases. Further work with heavier substituent groups is in progress.

sec-Dodecyl ethers of ethyleneglycol, 2-chloroethanol, and 1,3-dichloro-2-propanol have been prepared by reacting 1-dodecene with the corresponding substituted alcohol in the presence of BF3 as a catalyst.