Odor and chemesthesis from brief exposures to TXIB

An experiment explored ability of subjects to detect vapors of the plasticizer TXIB (2,2,4-trimethyl-1,3-pentanediol diisobutyrate) and ethanol via olfaction and via ocular and nasal chemesthesis, i.e. chemically stimulated feel. Testing, tailored to the sensitivity of each subject, produced psychometric functions for individuals. Olfactory detection of TXIB began at concentrations below 1 ppb (v/v), with 50% correct detection at 1.2 ppb. (Comparable detection for ethanol occurred almost two orders of magnitude higher.) Chemesthetic detection of TXIB began at about 500 ppb, with 50% correct detection at 2.1 ppm for the eye and 4.6 ppm for the nose, both close to saturated vapor concentration. (Comparable detection for ethanol occurred essentially three orders of magnitude higher.) Suggestions that TXIB plays a role in generation of irritative symptoms at concentrations in the range of parts-per-billion need to reckon with a conservatively estimated 200-fold gap between the levels putatively 'responsible' for the symptoms and those even minimally detectable via chemesthesis. Neither the variable of exposure duration nor that of mixing offers a likely explanation. Inclusion of ethanol in the study allowed comparisons pertinent to issues of variability in human chemoreception. An interpretation of the psychometric functions for individuals across materials and perceptual continua led to the conclusion that use of concentration as the metric of detection in olfaction inflates individual differences. PRACTICAL IMPLICATIONS: This study indicated that the plasticizer TXIB could contribute odor at concentrations in the range of parts-per-billion, but could hardly contribute sensory irritation per se, as alleged in reports of some field studies where TXIB has existed amongst many other organic compounds.     

GC-MS法测定白酒接触塑料材料中非邻苯类塑化剂TXIB的迁移量

该研究采用液液萃取结合气相色谱-质谱(GC-MS)法建立了白酒接触用塑料材料中2,2,4-三甲基-1,3-戊二醇双异丁酸酯(TXIB)迁移量的测定方法.方法采用食品模拟物对常见塑料材料样品进行迁移试验后,得到模拟浸泡液,选择正己烷作为萃取溶剂对模拟浸泡液进行萃取,萃取溶剂体积为2 mL,震荡萃取时间为1 min,萃取液...     

TXIB对Mextral973H从铜氨溶液中萃取铜及氨的影响研究

以Cu-NH_3-NH_4Cl-H_2O体系为研究对象,TXIB(2,2,4-三甲基-1,3-戊二醇双异丁酸酯)为改质剂,考察TXIB用量、萃取剂浓度、萃取相比、水相铜浓度、氨浓度等对萃取剂Mextral973H从铜氨溶液中萃取铜及氨的影响。结果表明,TXIB的使用可以显著降低氨的共萃而不影响铜的萃取。在萃取相比O/A=1/1、有机相浓度20%、铜浓度18.0g/L、氨浓度84.0g/L的条件下,向有机相中添加10%的TXIB后,铜萃取率由60.44%变化为60.20%,有机相共萃氨量从410.2mg/L降至154.8mg/L。