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Mar 11, 2016 - ... Benito Juárez, Crédito Constructor, 03940 Ciudad de México, D.F, ... children living in Mexico City consume and its association with their ...
Environmental Research 147 (2016) 497–502

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Lead in candy consumed and blood lead levels of children living in Mexico City Marcela Tamayo y Ortiz a,b, Martha María Téllez-Rojo b,n, Howard Hu c, Mauricio Hernández-Ávila b, Robert Wright d, Chitra Amarasiriwardena d, Nicola Lupoli e, Adriana Mercado-García b, Ivan Pantic f, Héctor Lamadrid-Figueroa b a

National Council of Science and Technology, Avenida Insurgentes Sur 1582, Benito Juárez, Crédito Constructor, 03940 Ciudad de México, D.F, Mexico National Institute of Public Health, Universidad No. 655 Colonia Santa María, Ahuacatitlán, Cerrada Los Pinos y Caminera C.P. 62100, Cuernavaca, Morelos, Mexico c University of Toronto, Dalla Lana School of Public Health, 6, 155 College St, Toronto, ON, Canada M5T 3M7 d Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, 1428 Madison Ave, New York, NY 10029, United States e Harvard T.H. Chan School of Public Health, 677 Huntington Ave, Boston, MA 02115, United States f National Institute of Perinatology, Calle Montes Urales #800, Miguel Hidalgo Lomas Virreyes, 11000 Ciudad de México, D.F, Mexico b

art ic l e i nf o

a b s t r a c t

Article history: Received 18 December 2015 Received in revised form 2 March 2016 Accepted 3 March 2016 Available online 11 March 2016

Background: Recent studies have shown that lead exposure continues to pose a health risk in Mexico. Children are a vulnerable population for lead effects and Mexican candy has been found to be a source of exposure in children. There are no previous studies that estimates lead concentrations in candy that children living in Mexico City consume and its association with their blood lead level. Objectives: To evaluate whether there is an association between reported recent consumption of candies identified to have lead, and blood lead levels among children in Mexico City. Methods: A subsample of 171 children ages 2–6 years old, from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohort study was assessed between June 2006 and July 2007. The candy reported most frequently were analyzed for lead using ICP-MS. The total weekly intake of lead through the consumption of candy in the previous week was calculated. Capillary blood lead levels (BLL) were measured using LeadCare (anodic stripping voltammetry). Results: Lead concentrations Z 0.1 ppm, the FDA permitted level (range: 0.13–0.7 ppm) were found in 6 samples out of 138 samples from 44 different brands of candy. Median BLL in children was 4.5 mg/dl. After adjusting for child’s sex, age, BMI, maternal education & occupation, milk consumption, sucking the candy wrapper, use of lead-glazed pottery, child exposure behavior, living near a lead exposure site and use of folk remedies, an increase of 1 mg of lead ingested through candy per week was associated with 3% change (95% CI: 0.1%, 5.2%) in BLL. Conclusions: Although lead concentrations in candy were mostly below the FDA permitted level, high lead concentrations were detected in 4% of the candy samples and 12% of brands analyzed. Although candy intake was modestly associated with children’s BLL, lead should not be found in consumer products, especially in candy that children can consume due to the well documented long-lasting effect of lead exposure. & 2016 Elsevier Inc. All rights reserved.

Keywords: Lead Children Candy Mexico

1. Introduction n Correspondence to: Center for Nutrition Research and Health, Universidad No. 655 Colonia Santa María, Ahuacatitlán, Cerrada Los Pinos y Caminera C.P. 62100, Cuernavaca, Morelos, Mexico. E-mail addresses: [email protected] (M. Tamayo y Ortiz), [email protected] (M.M. Téllez-Rojo), [email protected] (H. Hu), [email protected] (M. Hernández-Ávila), [email protected] (R. Wright), [email protected] (C. Amarasiriwardena), [email protected] (N. Lupoli), [email protected] (A. Mercado-García), [email protected] (I. Pantic), [email protected] (H. Lamadrid-Figueroa).

http://dx.doi.org/10.1016/j.envres.2016.03.007 0013-9351/& 2016 Elsevier Inc. All rights reserved.

Lead exposure continues to represent an important health risk for the Mexican population. In a recent review, Caravanos et al. concluded that lead has a significant effect on the pediatric burden of disease, implying a loss of more than 5 IQ points for more than 15% of the population, and because of lead-induced mild mental retardation, over eight hundred thousand disability-adjusted lifeyears for children 0–4 years old (Caravanos et al., 2014). Candy are

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part of Mexican children’s diet, 31.3% of children aged 1–4 and 36.5% children 5–9 years of age ate candy every day (Flores-Huerta et al., 2006). During the 1990s and early 2000s, high concentrations of lead were found repeatedly in Mexican candy (CDC, 2002, 1998; Kim et al., 2008; Lynch et al., 2000; Maxwell and Neumann, 2008; Medlin, 2004). According to the Centers for Disease Control and Prevention (CDC), of 1000 cases of elevated blood lead levels in children reported to the California Department of Health Services between May 2001 and January 2002, 150 were associated with children eating Mexican candy (CDC, 2002). In their special weekly report from April 30, 2004, the Orange County Register-Excelsior from California displayed an extensive investigation on this subject (McKim et al., 2004). The main suspected source of lead in the candy was powdered chili pepper used in their production. However, lead has been found in non-spicy treats such as in chocolates and candies (mean 0.93 ppm, range: 0.049–8.04 ppm), chewing gums and candies marketed in Turkey (mean 0.746 ppm, range: 0.031–2.46 ppm) (Duran et al., 2009), and chocolate from Brazil (range: o0.02–0.14 ppm) (Villa et al., 2014). Since November 2006, the U.S. Food and Drug Administration (FDA) decreased the “recommended lead concentration in candy likely to be consumed frequently by small children” from 0.5 to 0.1 ppm (limit set for producers) and implemented a surveillance program, testing lead concentrations in candy periodically (FDA, 2006a). Children are at greater risk of being affected by lead due to their metabolism, as well as their exposure sources and pathways (often as a result of crawling and hand-to-mouth behavior) (Bellinger, 2004). A child absorbs 50% of the lead ingested compared to 10% by an adult; for every microgram of lead that a child ingests his or her blood lead level increases by 0.16 mg/dl (ATSDR, 2007). The FDA has established a provisional total tolerable daily intake level (PTTIL) of 6 mg for childrenr five years old, 25 mg for pregnant women and 75 mg for adults (limits set for consumers) (FDA, 2006b). In Mexico there are no official regulations for lead concentrations in candy or for daily lead intake. The current norm established by the health ministry for non-occupational blood lead levels NOM-199-SSA1-2000, sets the limit at 10 mg/dl (SSA, 2000) and in the US since 2012 the limit was set to 5 mg/dl (CDC, 2012). However, there is enough evidence that even at lower blood concentrations there can be irreversible damage in neurodevelopment, neuropsychological function, and intellectual impairment (Bellinger, 2013; Boucher et al., 2014; Claus Henn et al., 2012; Grandjean and Landrigan, 2014; Kordas et al., 2015). In this study, we collected information on candy consumed by children and other sources of exposure to lead that may include the use of lead-glazed pottery to cook, store or serve food (Caravanos et al., 2014; Hernandez Avila et al., 1991), folk remedies (Gorospe and Gerstenberger, 2008) and candy wrappers (Lynch et al., 2000). We report the lead concentrations found in the most consumed candy by children from Mexico City and the association between estimated weekly intake of lead through candy and their blood lead levels.

2. Methods 2.1. Study population Between June 2007 and July 2008, we invited a subsample of children between 2 and 6 years of age from the third birth cohort (2001–2006) of the ELEMENT project to participate in our study. This cohort has followed 393 mother-infant pairs since 2001 in Mexico City, and has been described in detail previously (Ettinger et al., 2009). Briefly, women were recruited at clinics belonging to the Mexican Social Security System, and followed through

pregnancy. After birth, dyads were seen every six months with the main objective of studying prenatal exposure to lead and child development. All children who attended our research clinic during the study period, whose parent or guardian signed a consent letter and who had a capillary blood sample taken at the time of visit were included in this study (n ¼171). We compared our study participants to children from the same cohort who had a follow-up visit in the same month range (14 months) previous to our study, from April 2006 to May 2007 (n ¼182). Questionnaires were administered by trained social workers at the National Institute of Perinatology. The protocol and all questionnaires used for this study were previously approved by the ethics committee of the National Institute of Public Health, Mexico. 2.2. Lead in blood We performed a capillary blood lead test by anodic stripping voltammetry using the LeadCare System by ESA laboratories (detection range from 1.4 to 65 mg/dl). A trained nurse cleaned the child’s non-dominant index finger tip with alcohol and obtained a drop of capillary blood through a finger prick. The test was always carried out in the same lead-free research facility. The test has shown to have a correlation of 40.90 with venous blood (D’Souza et al., 2002; Schlenker, 1994). 2.3. Candy consumption and other covariate information To estimate the association between lead concentrations in consumed candy and blood lead levels, we focused on candy that was eaten during a period of one week going back from the day of the visit. We asked the mother or guardian about the brand, type (chocolate, chewing gum, lollipop, powder, gel, etc), and amount of up to 5 different candy consumed by the child during the previous week from the day of the visit. A staff member, blind to the child’s blood lead level, applied this questionnaire. We registered the child’s age, sex, weight and height as well as maternal occupation and education. We also collected information on lead exposure sources that have been previously reported in the literature (Schnur and John, 2014): eating/sucking chipped paint from walls, crayons, graphite pencils, colored pencils, painted toys and playdough, living near a printing house, a gas station, a plumbers workshop, a carpenter or wood-processing shop, a battery repair/recycling/manufacturing shop, a paint/ varnish factory, a ceramics factory/workshop, a refinery or a smelter, child’s habit to suck the candy wrappers (Fuortes and Bauer, 2000), daily milk consumption (assuming this could reflect a healthier behavior and be protective against lead (Hernandez-Avila et al., 1997)), use of folk remedies (CDC, 2002; Gorospe and Gerstenberger, 2008) and use of traditional lead-glazed ceramics for cooking/ storing food (Azcona-Cruz et al., 2010; Caravanos et al., 2014; Hernandez Avila et al., 1991). 2.4. Lead in candy analysis We measured lead concentrations in five samples from each of the 20 most frequently reported brands in the consumption questionnaire. Candies were purchased in August 2008 from 3 different stores found in the general vicinity to the IMSS clinics were participants were recruited because they are located near the participant’s homes and to avoid having samples from the same production batch. These candy were analyzed in September of the same year. Previously, in July 2007, in order to standardize the laboratory method for the determination of lead, we analyzed 38 candy samples from 28 different brands. The candy brands were chosen from lists of reported candy with high lead (CDPH, 2013; The Orange County register, 2004). Due to the financial constraints

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of our study, we were not able to analyze the candy wrappers and we were limited to 100 samples in the 2008 analysis. All analyses were performed at the Harvard T.H. Chan School of Public Health Trace Metals Laboratory. A total of 138 candy samples from 44 different brands (4 brands were repeated in 2007/2008) were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Candy samples were weighed (  2 g) into a 50 mL plastic tube and digested with 2 mL of concentrated nitric acid for 24 hours and then diluted to 25 mL with deionized water. Acid-digested samples were analyzed by an inductively coupled plasma mass spectrometer (Elan 6100, Perkin Elmer, Norwalk, CT). Analyses were performed using an external calibration method with thallium as the internal standard for lead. Quality control measures included analysis of the initial calibration verification standard [National Institute of Standard and Technology Standard Reference Material 1643e (trace elements in water, Gaithersburg, MD)], a 1 ng/g mixed element standard solution containing lead, continuous calibration standards, and a procedural blank. Certified Reference Material GBW 07601 was used as the quality control sample. We used a large preparation of GBW 07601 (2 g /Liter) to monitor day-to-day variation. Results were given as the average of five replicate measurements. The detection limit for lead was 0.2 ng/g. Recovery of the analysis of the quality control standard by this procedure is 90–110% with approximately 0.05 of coefficient of variation for within the day analysis. Between-assay coefficient of variation for lead was 0.03. 2.5. Calculation of the previous week lead intake through candy consumption A child could report consuming up to 5 different candy brands during the previous week. For each child and each of the candy brands he or she reported we calculated the weekly lead intake through a specific candy brand consumption based on its serving size, the reported amount of this candy consumed during the week, and its mean lead concentration found in our laboratory analysis:

Weekly Pb specific candy (μg per week ) = [SS ]*[CC ]*[Pb concentration] where [SS ¼serving size, units] is taken directly from the candy packaging (g), [CC¼candy consumption, units] is the number of pieces of the selected candy consumed per week, [Pb concentration] is the mean lead concentration in the selected candy brand [mg/g]. The total lead intake through candy consumption for each child was then calculated by adding the estimated weekly lead intake for each of the candy reported (micrograms of lead per week). 2.6. Statistical analysis We used linear regression models to investigate the association between log-transformed child’s blood lead levels and past-week lead-through-candy ingestion. We adjusted the models by child’s sex, age, cups of milk per day, sucking the candy wrapper, use of lead-glazed pottery and folk remedies.

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Table 1 Characteristics of study participants and nonparticipants (mean 7 SD, min, max, or %). Characteristic

Participantsa Nonparticipantsb

Sex (% male) BMI (kg/m2) Age (min, max) Lead in blood (mg/dl) Lead in candy eaten during the past week (mg/week) Candy pieces per week No. cups daily milk consumption Child sucks candy wrappers (% yes) Lead exposure risk behaviord (% yes) Use of lead-glazed pottery at home (% yes) Residence nearness to lead industrye (% yes) Use of home remedies at home (% yes) Maternal education (school years) Maternal Occupation (% house work vs other)

48 15.8 7 1.7 4 (2, 6) 4.5 7 1.9 1.2 7 2.7

48 16.3 7 2c 4 (2,5) 5.17 1.7c NA

19 (0, 39) 3 (0, 7) 18 49 24 10 38 107 3 63

NA NA NA 45 21 26 NA 117 3 NA

a

n ¼ 171. n ¼ 182 children from the same cohort who visited our study center from April 2006-May 2007. c Statistically different from participants. d Eating/sucking chipped paint from walls, crayons, graphite pencils, colored pencils, painted toys and playdough. e Living near a printing house, a gas station, a plumbers workshop, a carpenter or wood-processing shop, a battery repair/recycling/manufacturing shop, a paint/ varnish factory, a ceramics factory/workshop, a refinery or a smelter. b

range of none to 32 (Table 1). Most of the study participant characteristics did not differ from non-participants, except for BMI and blood lead levels which were greater in non-participants. There were 175 different candy brands and types reported as eaten by children during the previous week. These included lollipops, chocolates, chewing gum, tamarinds, gels, taffy, powdered chili and hard candy. Tables 2 and 3 show the results of the lead concentrations and content per serving piece for the candy brands analyzed. Overall, lead concentrations in candy samples were below 0.1 ppm, the FDA permissible limit for candy producers. Samples from 6 candy brands had lead concentrations over this limit (Rockaleta Diablo (0.70 ppm), Tiramindo (0.37 ppm), Ricaleta Chamoy (0.19 ppm), Tutsi Pop (0.13 ppm), Indimarimbas (0.22 ppm) and Gudu Pop Chile (0.16 ppm)). We found a significant association between the previous week lead intake through the consumption of candy and children’s blood lead levels, Fig. 1 shows the partial residual plot of the adjusted association (graphing the exposure of interest and outcome with all covariates in the model).. Because we used the log transformed values of lead, we also present our results in percent change in the blood lead levels. The unadjusted model had a regression coefficient (β)¼0.03, p value 0.04, indicating that for every increase of 1 mg of lead ingested through candy per week, blood lead levels had a 2.6% change (95% C.I. 0.19, 5.05); and this remained statistically significant with the same magnitude when adjusted by other covariates (Table 4). Lead-through candy consumption, age and sex were significantly associated with the child’s blood lead level. Other than the use of lead-glazed pottery (which was marginally statistically associated, p ¼0.09), no other covariate was associated with blood lead levels.

3. Results 4. Discussion Children were between 2 and 6 years of age and had a median blood lead level of 4.5 mg/dl (range from lower than the limit of detection (1.4) to 24.5 mg/dl). The median of lead per week ingested was 0.27 mg (range 0–16.1 mg). On average, children reported eating less than three candies per day (19 per week) with a

The candy samples analyzed in our study were mostly below the FDA permitted lead concentration limit. Still, 6 samples exceeded it and 1 of them more than doubled the PTTIL for children. Although we found an association between the previous week

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Table 2 Lead concentrations and lead content per serving piece (sp) in the 20 most reported candy consumed during the past week. Candy comercial name

Mean Pb (ppm)

Pb range (ppm)

Weight/sp (g)

Average Pb/sp (lg)

Highest Pb/sp (lg)

Brinquitos Bubbaloo Carlos V Cazuelita Crack Ups Crayón Duvalín Gudu Pop con Chile Lucas Muecas Miguelito Panzón Pelón Pelo Rico Pelonetes Pollito Alvro Pulparindo Skwinkles Sponge bob Tama Roca Tutsi Pop Winnis Taffy

0.02 0.01 0.01 0.03 0.00 0.00 0.01 0.10 0.01 0.05 0.00 0.00 0.00 0.02 0.01 0.01 0.01 0.01 0.03 0.02

0.02–0.03 0.01–0.03 0.03–0.01 0.02–0.05 o DL-0.00 o DL-0.00 0.00–0.01 0.06–0.16 0.01–0.02 0.04–0.06 o DL-0.00 0.00–0.02 o DL-0.00 0.01–0.03 0.00–0.01 0.00–0.01 0.00–0.01 0.00–0.01 0.01–0.13 0.01–0.03

3 5.3 10 12 40 32 15 10 20 5 40 35 35 14 14 19 35 20 20 1

0.07 0.07 0.05 0.37 0.02 0.00 0.13 0.96 0.29 0.24 0.06 0.05 0.05 0.24 0.11 0.10 0.21 0.20 0.65 0.00

0.08 0.14 0.08 0.58 0.08 0.13 0.17 1.57 0.40 0.29 0.12 0.67 0.11 0.35 0.14 0.11 0.25 0.28 2.58 0.03

Table 3 Lead concentrations and lead content per serving piece in 38 candy used to establish laboratory method. Pb Range (ppm)

Weight/ sp(g)

Candy comercial name

Mean Pb (ppm)

Chupachupsa Chupirula Paleta Payasoa Pollito Alvroa,b Aciditasc EnchiladasPaletasc Paleton Coronac Single test Bubulubu Chacachaca Cuchara Mix Gomilocas Dientes Gomilocas Ranitas Gomita Hormiga Indy Marimbas Kinder Sorpresa Pelon pelo ricob Picolero Con Chiliquido Piñaleta Rebanaditas Sandia Rellerindos Ricaleta Chamoy Rockaleta Diablo Selz Soda Sponge Bobb Sweet Tarts Tama Rocab Tiramindo Turin Conejito

0.02 0.02–0.03 15 0.04 0.03–0.04 15 0.02 0.01–0.02 40 0.02 0.02–0.03 14 0.01 0.01–0.03 5 0.02 0.01–0.02 15 0.04 0.04–0.05 25 Pb (ppm) Weight/sp(g) 0.01 20 0.05 30 0.03 16 0.01 150 0.00 150 0.02 20 0.22 35 ND 20 0.01 35 0.09 100

a b c

0.03 0.03 0.01 0.19 0.70 0.01 0.01 0.00 ND 0.37 0.01

20 20 11 15 20 5 35 51 60 20 20

Average Pb/ Highest sp (lg) Pb/sp (lg) 0.34 0.53 0.80 0.34 0.07 0.29 1.08

0.38 0.66 0.92 0.42 0.14 0.33 1.18 Pb/sp (lg) 0.20 1.41 0.47 1.29 0.39 0.44 7.68 ND 0.28 8.53 0.66 0.67 0.08 2.88 14.02 0.06 0.18 0.14 ND 7.41 0.24

two samples were analyzed. candy type repeated in 2008 analysis. three samples were analyzed.

consumption of candy and blood lead levels in the children, we did not analyze the candies the child actually ate. However, the candy was purchased shortly after we collected the consumption information and we have no reason to believe that in that time frame candy production would change abruptly. Although weekly lead-through-candy intake was associated with a modest change (3%) in children’s blood lead levels, this represents the change for each mg of lead. As can be observed in

Fig. 1. Association between lead-through-candy weekly intake (mg/week) and child’s blood lead levels (lnpb), adjusted for child’s sex, age, BMI, milk cups per day, sucking candy wrapper, use of lead-glazed pottery, lead exposure risk behavior, living near lead exposure site, use of home remedies, maternal education (school years) and occupation. Table 4 Association between lead-through-candy intake and child blood lead levels.

Lead-through candy consumption (mg/week) Sex (girl) Age BMI (kg/m2) Maternal education (school years) Maternal occupation Milk cups per day Sucking candy wrappers (yes) Use of lead-glazed pottery (yes) Child exposure risk behaviora Living near lead exposure siteb Use of folk remedies (yes)

β

p value % change 95% CI

0.03

0.04

2.60

(0.08, 5.18)

 0.13 0.14 0.00  0.00

0.05 0.02 0.92 0.86

 14.06 14.49 0.19  0.20

(  30.02,  0.07) (2.18, 28.28) (  3.58, 3.98) (  2.56, 2.15)

0.01  0.02  0.02 0.25 0.11  0.07  0.06

0.18 0.53 0.86 0.09 0.12 0.52 0.38

0.60  1.92  1.52 28.01 11.35  7.34  6.07

(  0.29, 1.49) (  8.05, 4.05) (  20.16, 16.59) (  3.84, 70.15) (  2.89, 27.57) (  33.18, 15.58) (  21.02, 7.57)

a eating/sucking chipped paint from walls, crayons, graphite pencils, colored pencils, painted toys and playdough. b living near a printing house, a gas station, a plumbers workshop, a carpenter or wood-processing shop, a battery repair/recycling/manufacturing shop, a paint/ varnish factory, a ceramics factory/workshop, a refinery or a smelter.

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Fig. 1, some of our study participants had 45 mg of lead per week through candy intake, therefore children that consume 5 or 10 mg of lead through candy, would translate in a 13.72% and 29.32% change respectively in their blood lead levels. Our results for the association are probably underestimates since we were only able to analyze samples from 22% of the reported candy brands. Additionally, we limited the amount of candy brands reported to 5 per week. Therefore, the calculated weekly lead intake through candy ingestion for each child is the lower bound estimate of the lead intake through candy. If lead concentrations for more of the candy reported had been analyzed, it is likely this association could have been stronger. Many children mentioned eating candy but couldn’t remember a specific brand. Mexico has an important tradition of homemade candies that varies from region to region and uses local ingredients, for example, tamarind candy is packed in lead-glazed ceramics, which leach lead into its contents (Azcona-Cruz et al., 2010). This particular type of candy was not reported by the children in the study, but has been found to have elevated levels of lead and it is widely sold and consumed throughout the country (McKim et al., 2004). We were unable to measure lead concentrations in the candy wrappers, however a federal regulation on lead content in ink was established 1993 and updated in April 2008 before we purchased the analyzed candy (SSA et al., 2008). In this study we found no association between sucking the candy wrappers and the children’s lead levels. The information we collected is based on memory recall by the children’s mothers or caregivers. Children could be spending time with other people, eating candy in school or other places and the mother/caregiver could not be aware of this. Therefore, we cannot rule out potential measurement misclassification which could bias our results in either direction. Our study included 47% of the cohort participants, a convenience sample defined by the date that the participants attended our research center (between June 2007 and July 2008). We did not select our participants based on any given characteristic that could bias our results. As can be seen in Table 1, nonparticipants did not differ in most of their characteristics except for having greater BMI’s and blood lead levels than participants. This difference would have not likely bias our results given that BMI was not a strong predictor of out outcome and further, blood lead levels were lower in our study participants. The number of candy analyzed was limited by our financial resources. Had we increased the number of candy to be analyzed, as mentioned above, it is likely that our estimates would be stronger and more precise. Other than milk consumption, during this study period we did not collect information on other food items/nutrients, furthermore it is unlikely that the intake of a certain food item could be associated with consumption of candy containing higher or lower lead and therefore would not confound our results. Mexico is an important producer of lead and it is well documented that populations living nearby lead mines have high blood lead levels as well as health outcomes derived from this (FloresRamírez et al., 2012). However, our study participants were all residents of Mexico City where there are no lead mines. Another important source of lead could be leaded gasolines, but this was completely eliminated in Mexico since 1997 (Schnaas et al., 2004; Téllez-Rojo and Gómez-Dantés, 2015). A recent study by Farias et al. showed similar lead concentrations in Mexican candy (mean 0.034, range 0.001–0.176 ppm). They didn’t find an association with the children’s blood lead levels, but the age of their participants, study site and number of candy analyzed was different than ours. (Farías et al., 2014). In 2013 Mexico exported 495 million dollars’ worth of candy, placing it among its top 10 export products (Chavez, 2014). Today it is

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possible to find international food products in the markets of most countries (Handley et al., 2007; Tehranifar et al., 2008), therefore regulations on lead and other toxic contents in food should be tightly regulated globally.

5. Conclusions Although most of the tested candy samples had lead concentrations below the FDA recommended level of 0.1 ppm, we found high concentrations of lead in some of the samples analyzed. Additionally our results show that past-week lead-throughcandy intake has an association with an association in blood lead levels of young children living in Mexico City. This evidence should be used to press both the companies to improve the quality of their products, and the government to have stricter laws and surveillance. Lead should not be found in any amount in any consumer products, especially those that children can have contact with.

Grants This work was supported by: U.S. National Institute of Environmental Health Sciences (NIEHS) grants P42-ES05947, R01ES07821, R01-ES014930, P30-ES00002; by Consejo Nacional de Ciencia y Tecnología (CONACyT) grant 4150M9405. The protocol and questionnaires used for this study were approved previous to the start of the study by the ethics committee of the National Institute of Public Health, Mexico. This study was reviewed and approved by the IRB committee of the National Institute of Public Health, Mexico registration number: CI 223 Code: 105–6134.

Acknowledgements We thank the Centro Médico ABC, México for their support with this research. This study was supported and partially funded by the National Institute of Public Health/Ministry of Health of Mexico.

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