Exposure to PollutionNCT03159013
Toxicokinetic Study of Lambda-cyhalothrin Biomarkers of Exposure
A study testing Exposure in people with Exposure to Pollution, run by Université de Montréal.
Trial summary
Exposure to pyrethroid pesticides is a growing concern in the workplace especially since they are also present in the diet of the general population. It is important to monitor human exposure to these contaminants. Read more about this study
- Who is it for?
- Ages 21 to 64 yearsHealthy volunteers can take part
- Conditions the study is for
- Exposure to Pollution
- What is being tested?
- Exposure
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 7 participants
- Where
- No sites listed yet
- Study dates
- 22 Sep 2016to 30 Apr 2017
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 21 to 64 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Good health
- Caucasian origin (same group to have less genetic variability)
Who cannot join
- Pyrethroid exposure at work or home (pet, garden)
- Any kidney or liver illness
About this study
Official title: La Lambda-cyhalothrine Comme Insecticide privilégié en Milieu Agricole: étude de la toxicocinétique de Biomarqueurs Pour le Suivi de l'Exposition Des Travailleurs
Exposure to pyrethroid pesticides is a growing concern in the workplace especially since they are also present in the diet of the general population. It is important to monitor human exposure to these contaminants. Exposure to pyrethroids may occur by multiple routes of exposure (oral, inhalation and dermal), such that it is difficult to assess absorbed doses from external exposure assessments. Biological monitoring, which consists of measuring urinary metabolites, is now recognized by the scientific community as a preferred approach to assess exposure to this type of compound. These metabolites are biotransformation products produced in the human body from the exposure compounds. However, interpretation of these biological monitoring data requires a proper knowledge of the kinetic behavior and thus the fate of the substance of interest in the human body in order to link levels of biomarkers in individuals to actual absorbed doses. Human kinetic data are still poorly documented in the case of pyrethroids. The study in volunteers exposed to pyrethroids in controlled conditions will allow acquiring new urinary and blood profiles to refine and address uncertainties in the toxicokinetics of lambda-cyhalothrin following oral and dermal exposure. Those data will serve to build a toxicokinetic model to predict absorbed doses in workers from urinary metabolite measurements and therefore better assess health risks.
Read the detailed description
Lambda-cyhalothrin is a synthetic pyrethroid pesticide widely used in Quebec to fight against pests in vegetable crops. In recent years, this pyrethroid has become one of the most used insecticides in these crops. However, there is a paucity of data on the biological behavior of this molecule in humans. Given the extensive use of this pyrethroid, it becomes essential to develop tools to properly assess exposure among workers largely in contact with pesticides during spraying or work in treated areas. Biological monitoring, which consists of measuring urinary metabolites is considered a preferred approach to evaluate absorbed doses of this type of product in the workplace, given the potentially combined exposure through the respiratory, dermal and oral routes. However, interpretation of biological monitoring data requires a good knowledge of the kinetic behavior of the substance of interest in the human body, to link biomarker levels among workers to actual absorbed doses. The overall objective of this project is to address the lack of knowledge on the toxicokinetics of biomarkers of exposure to lambda-cyhalothrin in humans for a better interpretation of routine biomonitoring data and hence health risks in exposed workers. First, a controlled kinetic study will be conducted in volunteers exposed acutely to a low oral dose of lambda-cyhalothrin (oral reference dose) followed by a cutaneous dose (of lambda-cyhalothrin formulation used by sprayers). The protocol will be similar to a previous one used by our team for toxicokinetic assessment of other pesticides. Secondly, a toxicokinetic model will be developed to simulate the kinetics of biomarkers of exposure to lambda-cyhalothrin, using data from the controlled kinetic study and based on a previous toxicokinetic model for related pyrethroids.
More specifically, volunteers will be exposed orally to 0.025 mg/kg body weight of lambda-cyhalothrin (single oral dosing). According to recent health risk assessment by the US Environmental Protection Agency (US EPA), volunteers should not incur any adverse effects relating to such dosing. Three weeks following oral dosing (to allow complete elimination of the compound from the body), the same volunteers will be exposed dermally to a lambda-cyhalothrin-based formulation used on crops. The formulation will be applied on a 40cm2 surface of the forearm at a concentration corresponding to the one used in the workplace (Matador 120EC). The treated area will not be washed for a period of 6 h. This type of application will be similar to that of exposed workers. Urinary and blood measurements of specific biomarkers of exposure to these insecticides will be performed. These biomarkers of exposure are already known from other studies and have been shown to be good bioindicators of exposure to pyrethroids. The kinetic profile will serve to link absorbed doses to blood and urinary concentrations of metabolites through time. Personal information on health status, diet and lifestyle will be documented. A total of 7 volunteers will spend a full day at the University during which they will be exposed to a low dose of pesticide. Blood and urinary samples will be collected. Four short visits of one hour will be needed for blood collections. Every urine void for a period of 84 hours will be collected in a different bottle. This whole process will be repeated twice to test two routes of exposure to this insecticide, oral (swallowed) and dermal (applied to the forearm).
The study in volunteers exposed to lambda-cyhalothrin in controlled conditions will allow acquiring new urinary and blood metabolite profiles to better understand their kinetic behavior and essential biological determinants of the observed profiles. These data can then be used in a toxicokinetic model to predict the main routes of exposure and associated absorbed doses in workers exposed to formulations containing lambda-cyhalothrin.
- Conditions
- Exposure to Pollution
- Being tested
- Exposure
- Keywords
- Pyrethroids, Lambda-cyhalothrin, Biomarkers, Toxicokinetics
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ExposureOther
Oral exposure: 0,025 mg/kg bw dissolved in oil, on day 1, with blood withdrawn on days 2,3,4.
Dermal exposure: 145 µl of commercial formulation (0,25 mg/kg bw) on 40 cm2 of forearm skin for 6 hours, on day 28, with blood withdrawn on days 29,30,31.
| Study group | Role | What they receive |
|---|---|---|
| Pesticide toxicokinetics- oral | Other | Exposure type: ORAL Toxicokinetics Receives: Other: Exposure |
| Pesticide toxicokinetics- dermal | Other | Exposure type: DERMAL Toxicokinetics Receives: Other: Exposure |
What is being measured
The primary outcome is the main question the study is designed to answer.
Toxicokinetic parameters of lambda-cyhalothrin elimination after oral and dermal exposure.
Elimination half-lives of biomarkers of exposure
Measured: 84-h post-treatment
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 May 2017
- Study start22 Sep 2016
- Primary completion19 Nov 2016
- Study completion30 Apr 2017
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (3)Papers the sponsor has linked to this study.
- Other trials for Exposure to PollutionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Crossover
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 7 participants (actual)
Sponsor and investigators
- Lead sponsor
- Université de Montréal
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Michèle Bouchard, Université de Montréal
- Investigators
- Michèle Bouchard, PhD, Principal investigator, Université de MontréalJonathan Côté, MSc, Principal investigator, Université de MontréalRania Khemiri, BSc, Principal investigator, Université de Montréal
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03159013
- Sponsor's protocol ID
- IRSST-2010-0009
- Status last verified
- May 2017
- First submitted
- 15 May 2017
- Last updated
- 19 May 2017
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Ratelle M, Cote J, Bouchard M. Time profiles and toxicokinetic parameters of key biomarkers of exposure to cypermethrin in orally exposed volunteers compared with previously available kinetic data following permethrin exposure. J Appl Toxicol. 2015 Dec;35(12):1586-93. doi: 10.1002/jat.3124. Epub 2015 Mar 13.
PubMed 25772368Ratelle M, Cote J, Bouchard M. Toxicokinetics of permethrin biomarkers of exposure in orally exposed volunteers. Toxicol Lett. 2015 Jan 22;232(2):369-75. doi: 10.1016/j.toxlet.2014.12.003. Epub 2014 Dec 8.
PubMed 25498136Cote J, Bonvalot Y, Carrier G, Lapointe C, Fuhr U, Tomalik-Scharte D, Wachall B, Bouchard M. A novel toxicokinetic modeling of cypermethrin and permethrin and their metabolites in humans for dose reconstruction from biomarker data. PLoS One. 2014 Feb 26;9(2):e88517. doi: 10.1371/journal.pone.0088517. eCollection 2014.
PubMed 24586336
Study at a glance
From the registry record, last updated by the sponsor on 19 May 2017. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- La Lambda-cyhalothrine Comme Insecticide privilégié en Milieu Agricole: étude de la toxicocinétique de Biomarqueurs Pour le Suivi de l'Exposition Des Travailleurs
- ClinicalTrials.gov ID
- NCT03159013
- Acronym / sponsor ID
- IRSST-2010-0009
- Conditions
- Exposure to Pollution
- Keywords
- Pyrethroids, Lambda-cyhalothrin, Biomarkers, Toxicokinetics
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 7 participants (actual)
- Lead sponsor
- Université de MontréalUniversity, hospital or other
- Study start
- 22 Sep 2016 (actual)
- Primary completion
- 19 Nov 2016 (actual)
- Study completion
- 30 Apr 2017 (actual)
- First posted
- 18 May 2017 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Exposure to pyrethroid pesticides is a growing concern in the workplace especially since they are also present in the diet of the general population. It is important to monitor human exposure to these contaminants. Exposure to pyrethroids may occur by multiple routes of exposure (oral, inhalation and dermal), such that it is difficult to assess absorbed doses from external exposure assessments. Biological monitoring, which consists of measuring urinary metabolites, is now recognized by the scientific community as a preferred approach to assess exposure to this type of compound. These metabolites are biotransformation products produced in the human body from the exposure compounds. However, interpretation of these biological monitoring data requires a proper knowledge of the kinetic behavior and thus the fate of the substance of interest in the human body in order to link levels of biomarkers in individuals to actual absorbed doses. Human kinetic data are still poorly documented in the case of pyrethroids. The study in volunteers exposed to pyrethroids in controlled conditions will allow acquiring new urinary and blood profiles to refine and address uncertainties in the toxicokinetics of lambda-cyhalothrin following oral and dermal exposure. Those data will serve to build a toxicokinetic model to predict absorbed doses in workers from urinary metabolite measurements and therefore better assess health risks.
Detailed description
Lambda-cyhalothrin is a synthetic pyrethroid pesticide widely used in Quebec to fight against pests in vegetable crops. In recent years, this pyrethroid has become one of the most used insecticides in these crops. However, there is a paucity of data on the biological behavior of this molecule in humans. Given the extensive use of this pyrethroid, it becomes essential to develop tools to properly assess exposure among workers largely in contact with pesticides during spraying or work in treated areas. Biological monitoring, which consists of measuring urinary metabolites is considered a preferred approach to evaluate absorbed doses of this type of product in the workplace, given the potentially combined exposure through the respiratory, dermal and oral routes. However, interpretation of biological monitoring data requires a good knowledge of the kinetic behavior of the substance of interest in the human body, to link biomarker levels among workers to actual absorbed doses. The overall objective of this project is to address the lack of knowledge on the toxicokinetics of biomarkers of exposure to lambda-cyhalothrin in humans for a better interpretation of routine biomonitoring data and hence health risks in exposed workers. First, a controlled kinetic study will be conducted in volunteers exposed acutely to a low oral dose of lambda-cyhalothrin (oral reference dose) followed by a cutaneous dose (of lambda-cyhalothrin formulation used by sprayers). The protocol will be similar to a previous one used by our team for toxicokinetic assessment of other pesticides. Secondly, a toxicokinetic model will be developed to simulate the kinetics of biomarkers of exposure to lambda-cyhalothrin, using data from the controlled kinetic study and based on a previous toxicokinetic model for related pyrethroids.
More specifically, volunteers will be exposed orally to 0.025 mg/kg body weight of lambda-cyhalothrin (single oral dosing). According to recent health risk assessment by the US Environmental Protection Agency (US EPA), volunteers should not incur any adverse effects relating to such dosing. Three weeks following oral dosing (to allow complete elimination of the compound from the body), the same volunteers will be exposed dermally to a lambda-cyhalothrin-based formulation used on crops. The formulation will be applied on a 40cm2 surface of the forearm at a concentration corresponding to the one used in the workplace (Matador 120EC). The treated area will not be washed for a period of 6 h. This type of application will be similar to that of exposed workers. Urinary and blood measurements of specific biomarkers of exposure to these insecticides will be performed. These biomarkers of exposure are already known from other studies and have been shown to be good bioindicators of exposure to pyrethroids. The kinetic profile will serve to link absorbed doses to blood and urinary concentrations of metabolites through time. Personal information on health status, diet and lifestyle will be documented. A total of 7 volunteers will spend a full day at the University during which they will be exposed to a low dose of pesticide. Blood and urinary samples will be collected. Four short visits of one hour will be needed for blood collections. Every urine void for a period of 84 hours will be collected in a different bottle. This whole process will be repeated twice to test two routes of exposure to this insecticide, oral (swallowed) and dermal (applied to the forearm).
The study in volunteers exposed to lambda-cyhalothrin in controlled conditions will allow acquiring new urinary and blood metabolite profiles to better understand their kinetic behavior and essential biological determinants of the observed profiles. These data can then be used in a toxicokinetic model to predict the main routes of exposure and associated absorbed doses in workers exposed to formulations containing lambda-cyhalothrin.
Study design
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Crossover
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Pesticide toxicokinetics- oral | Other | Other: ExposureExposure type: ORAL Toxicokinetics |
| Pesticide toxicokinetics- dermal | Other | Other: ExposureExposure type: DERMAL Toxicokinetics |
Who may qualify
- Ages
- 21 to 64 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (2 listed)
- Good health
- Caucasian origin (same group to have less genetic variability)
Key exclusion criteria (2 listed)
- Pyrethroid exposure at work or home (pet, garden)
- Any kidney or liver illness
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ExposureOral exposure: 0,025 mg/kg bw dissolved in oil, on day 1, with blood withdrawn on days 2,3,4. Dermal exposure: 145 µl of commercial formulation (0,25 mg/kg bw) on 40 cm2 of forearm skin for 6 hours, on day 28, with blood withdrawn on days 29,30,31. | Other | Pesticide toxicokinetics- dermal, Pesticide toxicokinetics- oral |
Primary outcome
Toxicokinetic parameters of lambda-cyhalothrin elimination after oral and dermal exposure.
Time frame: 84-h post-treatment
Elimination half-lives of biomarkers of exposure
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 May 2017.
- Background: PubMed 25772368Ratelle M, Cote J, Bouchard M. Time profiles and toxicokinetic parameters of key biomarkers of exposure to cypermethrin in orally exposed volunteers compared with previously available kinetic data following permethrin exposure. J Appl Toxicol. 2015 Dec;35(12):1586-93. doi: 10.1002/jat.3124. Epub 2015 Mar 13.
- Background: PubMed 25498136Ratelle M, Cote J, Bouchard M. Toxicokinetics of permethrin biomarkers of exposure in orally exposed volunteers. Toxicol Lett. 2015 Jan 22;232(2):369-75. doi: 10.1016/j.toxlet.2014.12.003. Epub 2014 Dec 8.
- Background: PubMed 24586336Cote J, Bonvalot Y, Carrier G, Lapointe C, Fuhr U, Tomalik-Scharte D, Wachall B, Bouchard M. A novel toxicokinetic modeling of cypermethrin and permethrin and their metabolites in humans for dose reconstruction from biomarker data. PLoS One. 2014 Feb 26;9(2):e88517. doi: 10.1371/journal.pone.0088517. eCollection 2014.
- U.S. EPA (2004). Lambda-cyhalothrin and an isomer Gamma-cyhalothrin; Tolerances for residues. U.S. Environmental Protection Agency. Federal Register 69(68): 18480-18489.Link provided by the sponsor.
- IRSST (2016). Développement et application d'une approche pour l'évaluation de l'exposition des travailleurs agricoles aux pyréthrinoïdes. R-936. 188 pagesLink provided by the sponsor.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Michèle Bouchard, PhD principal investigator
Université de Montréal
Jonathan Côté, MSc principal investigator
Université de Montréal
Rania Khemiri, BSc principal investigator
Université de Montréal
Questions about this trial
What is this clinical trial studying?
A study testing Exposure in people with Exposure to Pollution, run by Université de Montréal.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 19 May 2017. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Toxicokinetic parameters of lambda-cyhalothrin elimination after oral and dermal exposure. (time frame: 84-h post-treatment). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03159013, which also lists 3 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 19 May 2017.