Grantee Research Project Results

2004 Progress Report: Longitudinal Study of Children's Exposure to Permethrin

EPA Grant Number: R829397
Title: Longitudinal Study of Children's Exposure to Permethrin
Investigators: Raymer, James H. , Hu, Ye A. , Akland, Gerald G.
Current Investigators: Raymer, James H. , Hu, Ye A. , Michael, L. C. , Studabaker, W.
Institution: Desert Research Institute
EPA Project Officer: Aja, Hayley
Project Period: February 18, 2002 through February 17, 2005 (Extended to July 17, 2006)
Project Period Covered by this Report: February 18, 2004 through February 17, 2005
Project Amount: $754,664
RFA: Children's Vulnerability to Toxic Substances in the Environment (2001) RFA Text | Recipients Lists
Research Category: Environmental Justice , Human Health , Children's Health

Objective:

The objectives of this research project are to: (1) investigate the time course of the redistribution of pyrethroid pesticides in various media following application and factors affecting the redistribution; (2) investigate the functional relationships across time between environmental media, personal measurements, and biological media; (3) estimate aggregate exposure after application and the importance of each exposure pathway; and (4) investigate the difference between the time course of pyrethroid pesticide metabolism in adults and children.

Progress Summary:

We are in the third year of this project, and we have requested a 1-year, no-cost extension. Dr. Raymer replaced Dr. Hu as the Principal Investigator (PI) when Dr. Hu left RTI. As shown in Figure 1, we have completed field sample collection, and we are well into sample analysis.

Figure 1. Children’s Permethrin Study Task Timeline

Sample Collection

The major achievement during the reporting period is the completion of field sample collection. Fifteen young children (<3 yrs old) from 13 homes (2 twin sets) with indoor application of pyrethroids have been followed successfully for up to 12 months. Among these 15 children, 66 percent completed the entire 12 month study (10 out of 15 participants), 93 percent completed at least 8 months of sample collection (14 out of 15 participants), and 100 percent completed at least 6 months of sample collection. Up to 17 sets of samples were collected, including air, surface wipes, toy wipes, hand wipes, body suits, duplicate diet, leftover food, morning urine samples (adults and children), video (eating and playing events), and questionnaires. Ages of the participants, the pesticide applied indoors, and applicable application information are shown in Table 1 and Table 2.

Table 1. Participant Age and Pesticide Application

Part ID	Child's Age at Beginning of Study (Months)	Child's BD	Pesticide	1st Application Planned for:	1st visit scheduled for:
001	14	6/17/2002	cyfluthrin	8/6/2003	8/4/03 at 4 pm
002	30	2/24/2001	deltamethrin	5/14/2003	5/9/03 at 10am
003 twin	26	6/25/2001	deltamethrin	5/14/2003	5/5/03 at 2 pm
004	45	11/4/1999	cyfluthrin and pyrethrins	5/27/2003	5/23/03 at 10 am
005 twin	25	7/17/2001	cypermethrin	12/2/2003	11/24/03 at 2 pm
006	22	10/5/2001	permethrin	7/14/2003	7/10/03 at 10 am
007	20	12/1/2001	deltamethrin	6/3/2003	6/2/03 at 3 pm
008	12	8/7/2002	cyfluthrin	7/9/2003	5/30/03 at 10 am
009 twin	25	7/17/2001	cypermethrin	12/2/2003	11/24/03 at 2 pm
010	25	7/30/2001	permethrin	09/25/2003	9/24/2003 at 12:30 pm
011	15	5/16/2002	permethrin	10/22/2003	10/20/2003 at 2 pm
012	29	3/3/2001	cypermethrin	6/24/2003	6/20/03 at 3 pm
013 twin	26	6/25/2001	deltamethrin	5/14/2003	5/5/03 at 2 pm
014	14	6/12/2002	permethrin and cypermethrin	8/20/2003	8/18/2003 at 2pm
015	14	6/2/2002	cypermethrin	10/3/2003	10/1/2003 at 4:30 pm

Table 2. Pesticides, Application Type, and Frequency

Participant ID	Pesticide Applied	Application Type	Frequency
001	cyfluthrin	professional	once
002	deltamethrin	professional	quarterly
003	deltamethrin	professional	quarterly
004	cyfluthrin and pyrethrins	professional	every other month
005	cypermethrin	professional	quarterly
006	permethrin and pyrethrin	self applicator	as needed during summer months
007	deltamethrin	professional	quarterly
008	cyfluthrin	professional	every other month
009	cypermethrin	professional	quarterly
010	permethrin	self applicator	as needed during fall months
011	permethrin	self applicator	as needed
012	cypermethrin	self applicator	as needed
013	deltamethrin	professional	quarterly
014	permethrin and cypermethrin	self applicator	as needed
015	cypermethrin	self applicator	as needed

Sample Analysis

Most of the samples have been extracted, and a portion of the samples have been analyzed. Table 3 provides preliminary results of target compound concentrations from surface wipes, hand wipes, and body suit samples. The results indicate substantial surface loading of the target compounds in these homes. The surface loading of cypermethrin and permethrin reached 230 ng/cm² and 210 ng/cm², respectively. Preliminary data from the hand wipes and body suits indicate potential for dermal uptake from the surfaces.

Table 3. Pyrethroid Loading or Amount in Handwipe, Surface Wipe, and Bodysuit Samples

SAMPLE MEDIUM	CONC. UNIT	CHEMICAL SPECIES	NO. OBS.	MEAN LOAD	STD. DEV.	MIN.	25TH PERC.	MEDIAN	75TH PERC.	MAX.	% MEAS.
Hand Wipe	ng/cm2^a	Deltamethrin	3	9	5.6	4.7	4.7	7.1	15	15	83
Hand Wipe	ng/cm2	Permethrin	2	6.6	7.5	1.3	1.3	6.6	12	12	86
Hand Wipe	ng/cm2	cis-Permethrin	2	2.9	3.3	0.54	0.54	2.9	5.3	5.3	75
Hand Wipe	ng/cm2	trans-Permethrin	4	2.1	3.1	0.069	0.37	0.77	3.7	6.6	88
Surface Wipe	ng/cm2	Cyfluthrin	21	4.9	7.8	0.29	0.88	1.7	3.6	27	35
Surface Wipe	ng/cm2	Cypermethrin	47	13	36	0.33	0.9	1.1	11	230	61
Surface Wipe	ng/cm2	Deltamethrin	81	10	13	0.64	2.6	6.2	13	61	83
Surface Wipe	ng/cm2	L-Cyhalothrin	40	14	19	0.064	0.92	11	19	80	54
Surface Wipe	ng/cm2	Permethrin	96	15	29	0.059	0.64	1.2	22	210	86
Surface Wipe	ng/cm2	cis-Permethrin	83	8.6	15	0.061	0.33	0.96	10	94	75
Surface Wipe	ng/cm2	trans-Permethrin	96	9.3	18	0.065	0.22	0.62	13	120	88
Body Suit	ng	L-Cyhalothrin	9	89	52	29	56	65	130	180	54
Body Suit	ng	Permethrin	10	2000	4100	20	93	230	750	13000	86
Body Suit	ng	cis-Permethrin	11	1100	1900	7.4	38	100	1700	5300	75
Body Suit	ng	trans-Permethrin	10	1600	2600	12	120	270	2400	7200	88

^aArea based on the average child hand surface area (one side, 143 cm²) from an earlier study.

We have completed the LC/MS/MS analysis of adult urine samples and urine samples from toilet-trained children. Pyrethroid metabolites 3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclo-propane) carboxylic acid (DCCA), 3-(2,2-dibromovinyl)-2,2dimethyl-(1-cyclo-propane) carboxylic acid (DBCA) and 3-phenoxybenzoic acid (3-PBA) concentrations in the analyzed samples are summarized in Table 4. Preliminary results indicate that metabolites were found in a small fraction of the samples (≤11%). Further statistical analysis will be performed at the completion of the remaining children’s urine samples. A key question is the temporal relationship between pesticide application and urine collection; this also will be investigated.

Table 4. Pyrethroid Metabolite Concentration in Urine Samples

SAMPLE MEDIUM	CONC. UNIT	CHEMICAL SPECIES	NO. OBS.	MEAN CONC.	STD. DEV.	MIN.	25TH PERC.	MEDIAN	75TH PERC.	MAX.	% MEAS.
Adult Urine	ng/mL	DCCA	208	0.016	0.06	0	0	0	0	0.55	4
Adult Urine	ng/mL	3-PDA	208	0.072	0.21	0	0	0.016	0.049	1.8	9
Adult Urine	ng/mL	DBCA	208	0.03	0.16	0	0	0	0	1.4	4
Child Urine	ng/mL	DCCA	57	0.02	0.065	0	0	0	0	0.34	7
Child Urine	ng/mL	3-PDA	57	0.069	0.14	0	0	0.032	0.054	0.72	11
Child Urine	ng/mL	DBCA	57	0.01	0.032	0	0	0	0	0.17	4

Future Activities:

The major goal for Year 4 of the project will be to complete sample analysis, data analysis, and reporting. Budgetary limitations will preclude analysis of the food samples. Even in the absence of those data, the major goals of the project will be achieved.

Journal Articles on this Report : 1 Displayed | Download in RIS Format

Publications Views
Other project views:	All 9 publications	4 publications in selected types	All 4 journal articles

Publications
Type	Citation	Project	Document Sources
Journal Article	Hu Y, Beach J, Raymer J, Gardner M. Disposable diaper to collect urine samples from young children for pyrethroid pesticide studies. Journal of Exposure Analysis and Environmental Epidemiology 2004;14(5):378-384.	R829397 (2002) R829397 (2003) R829397 (2004) R829397 (Final)	Abstract from PubMed

Supplemental Keywords:

pyrethroid pesticides, children, longitudinal study, disposable diapers, exposure modeling, exposure assessment, human exposure, human health risk,, RFA, Scientific Discipline, Health, Health Risk Assessment, Chemistry, Risk Assessments, Disease & Cumulative Effects, Children's Health, Biology, multi-pathway study, permethrin, pesticides, functional relationships, urinary metabolite, exposure, children, longitudinal study, body dosimeter, human exposure, exposure pathways, metabolism, exposure assessment

Progress and Final Reports:

Original Abstract

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.