Table 6.

An overview of selected studies looking at cotinine concentrations among children and youth globally

Authors and country	Type of study and cotinine sample	Size of population	Information of study	GM cotinine concentrations
Serum cotinine
Lazcano-Ponce et al. 2007 Mexico [31]	National Health Survey year 2000	76 and 83 children (<5 years)	Non-smoking homes and smoking homes	0.10 and 0.60 ng/ml for non-smoking and smoking homes respectively
Dove et al. 2010 USA [29]	National Health and Nutrition Examination Survey 1999-2006	11 486 non-smoking children/youth (<19 years)	Divided into 3 groups of extensive, limited and no SFL coverage	0.03 and 0.84 ng/ml for non-smoking and smoking homes in county with extensive SFL, 0.05 and 0.90 ng/ml for limited SFL, 0.07 and 1.13 ng/ml for no SFL coverage
Marano et al. 2009 USA [30]	National Health and Nutrition Examination Survey 2003-2006	5518 children/adolescents (3-19)	Non-smoking homes and smoking homes	0.05 and 1.05 ng/ml for non-smoking and smoking homes respectively
Salivary cotinine
Akhtar et al. 2007 Scotland [13]	National Survey from 111 schools	2559 and 2424 children (11 years) surveyed in 2006 and 2007 respectively	Children represented exposure before and after the implementation of SFL	0.14 and 0.07 ng/ml for children living in non-smoking homes before and after SFL 0.57 and 0.32 ng/ml for children living in smoking homes (father only smokes) after the SFL
Whitrow et al. 2010 England [32]	Survey in 2003-2004 among children from 51 schools in London	2311 children (11-13 years)	To differentiate exposure of SHS among whites and other ethnic groups	0.30 ng/ml and 0.84 ng/ml among White children living with no smokers and smokers (father only smokes) respectively
Jarvis et al. 2009 England [33]	Survey among children between year 1996 to 2007	13365 children (4-15 years)	Relationship between cotinine and smoking restriction in homes	0.22 ng/ml for non-smoking homes, 0.37 ng/ml (one smoker) and 0.71 ng/ml (two smokers) for smoke-free homes 1.67 ng/ml (one smoker) and 2.46 ng/ml (two smokers) for homes with no smoking restrictions
a Delpisheh et al. 2007 England [27]	Survey among children in low socioeconomic area in 2004	425 children (5-11 years)	Relationship between cotinine and respiratory symptoms	0.37 ng/ml for all children, 0.56 ng/ml among children living with a smoking mother and 0.38 ng/ml among children living with a smoking father
Holliday et al. 2009 Wales [14]	National Survey from 75 schools	1750 children (10-11)	Children represented exposure before and after the implementation of SFL	0.17 ng.ml for all children before the SFL 0.15 ng/ml for all children after the SFL

^a No specific value available for children living in non-smoking homes