Environmental ExposureEarly Phase 1NCT03802721
Pharmacokinetics of Benzo[a]Pyrene: Impact of Diet
A Early Phase 1 study testing [14C]-benzo[a]pyrene, Brussels sprouts before 50 ng dose and DIM supplement before 50 ng dose in people with Environmental Exposure, run by Oregon State University at 1 site in United States.
Trial summary
Evaluation of the pharmacokinetics for [14C]-benzo[a]pyrene ([14C]-BaP) and metabolites in plasma and urine over 48 hours following a 50 ng dose (5.4 nCi) alone, following 7 days' consumption of Brussels sprouts, and following 7 days' consumption of a supplement containing 3,3'-diindolylmethane (DIM). Read more about this study
- Who is it for?
- Ages 21 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Environmental Exposure
- What is being tested?
- [14C]-benzo[a]pyrene, Brussels sprouts before 50 ng dose and DIM supplement before 50 ng dose
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 7 participants
- Where
- 1 siteUnited States
- Study dates
- 24 Jan 2019to 1 Feb 2024
- Phase
- Early Phase 1
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Age 21-65 (inclusive)
- If female, must be post-menopausal or have had surgical sterilization to eliminate any possibility for fetal exposure
- Willing to defer blood donation for one month before, throughout, and one month after completion of study activities
- Willing to avoid consuming cruciferous vegetables, I3C or DIM supplements, smoked or cured meat or cheeses, or charcoal-grilled meats for 2 weeks prior to and during each study cycle (gas grilled foods acceptable)
- Health history review and physical assessment showing general good health, as determined by study physician. Acceptable physical exam may have been conducted as part of protocol 8233 or 8554 if subject has not had significant changes in health status.
Who cannot join
- Smoker (tobacco or other substances) or use of smokeless tobacco in past 3 months or living with smoker
- Regular use of medications that affect gut motility or nutrient absorption (e.g. cholestyramine, sucralfate, orlistat, pro- or anti-motility agents)
- History of gastrointestinal surgery (e.g. bariatric surgery, cholecystectomy) or gastrointestinal disorder (Crohn's disease, celiac disease, IBS, or colitis)
- Current or history of kidney or liver disease
- Prior high-dose 14C exposure from medical tests. (micro-dose 14C exposure not exclusionary)
- Occupational PAH exposure (e.g. roofers, asphalt pavers, fire-fighters, etc.)
- Regular use of indole-3-carbinol or DIM dietary supplements
- Allergy or intolerance to Brussels sprouts or similar foods
Trial locations and contacts
1 site in 1 country.
About this study
Evaluation of the pharmacokinetics for [14C]-benzo[a]pyrene ([14C]-BaP) and metabolites in plasma and urine over 48 hours following a 50 ng dose (5.4 nCi) alone, following 7 days' consumption of Brussels sprouts, and following 7 days' consumption of a supplement containing 3,3'-diindolylmethane (DIM).
Read the detailed description
The pharmacokinetics for [14C]-BaP and metabolites will be assessed by UHLPC-Accelerator Mass Spectrometry (AMS, Lawrence Livermore National Laboratory) in plasma and urine collected over 48 hours following oral doses of 50 ng dose (5.4 nCi) alone, following 7 days' consumption of Brussels sprouts, and following 7 days' consumption of a supplement containing 3,3'-diindolylmethane (DIM).
The investigators hypothesize that pre-administration of Brussels sprouts or DIM will alter [14C]-BaP metabolism and increase the rate of elimination consistent with predictions based on a previously developed Physiologically-Based Pharmacokinetic (PBPK) model for BaP. Briefly, this hypothesis will be tested by dosing individuals with 50 ng [14C]-BaP alone and, following a 3-week washout period, ingestion of about 50 g Brussels sprouts or 300 mg of 3,3'-diindolylmethane (DIM) supplement for 7 days prior to the [14C]-BaP micro-dose. The impact of the supplement and the whole food will be assessed with respect to alterations in uptake from the GI tract, metabolism and rate of elimination. The consumption of cruciferous vegetables will be assessed at the beginning of the study by completion of a dietary questionnaire to examine typical eating patterns in the previous 3 months and by collection and extraction of blood and urine to assay for DIM by LC/ESI-MS/MS-SRM). In addition, for each phase, urine will be assayed for DIM as an estimate of crucifer or DIM supplement intake.
In preclinical and clinical studies, administration of Brussels sprouts or DIM impacts the activity of the same enzymes responsible for the phase 1 (CYP1A1 and CYP1B1) and phase 2 enzymes (GSTM1, UGT, SULT). Monitoring changes in β-estradiol metabolites will confirm the mechanism of alteration in the metabolic profile of [14C]-BaP.
Metabolite profiles and kinetics of elimination are predicted to be consistent with a BaP physiologically based pharmacokinetic (PBPK) model developed by Pacific Northwest National Laboratory (PNNL). A non-smoker, not exposed occupationally, receives 270-700 ng of BaP daily; about 95% dietary. The WHO has set an estimated safe daily lifetime (70 year/70 Kg individual, cancer endpoint) exposure to BaP of 42-350 ng. This protocol represents de minimus risk.
- Conditions
- Environmental Exposure
- Being tested
- [14C]-benzo[a]pyrene, Brussels sprouts before 50 ng dose, DIM supplement before 50 ng dose
- Keywords
- Benzo[a]pyrene, Accelerator Mass Spectrometry, Polycyclic Aromatic Hydrocarbons, cruciferous vegetable, Brussels sprouts, 3,3'-diindolylmethane, DIM, indole-3-carbinol, I3C, PAH
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
[14C]-benzo[a]pyreneDrug
Also called Carcinogenic PAH environmental pollutant
Oral micro-dose (50 ng) (5.4 nCi)
Brussels sprouts before 50 ng doseDrug
Also called Brussels sprouts and carcinogenic PAH
Brussels sprouts for 7 days before 50 ng (5.4 nCi) dose of BaP
DIM supplement before 50 ng doseDrug
Also called Cruciferous vegetable supplement and carcinogenic PAH
DIM supplement for 7 days before 50 ng (5.4 nCi) dose of BaP and coadministration with DIM supplement
| Study group | Role | What they receive |
|---|---|---|
| 50 ng dose; Brussels sprouts before 50 ng dose; DIM supplement before 50 ng dose | Experimental | Cycle 1: Capsule containing 50 ng (5.4 nCi) [14C]-benzo[a]pyrene (BaP).
Cycle 2: Subjects will consume 50 g (about 1/2 cup) of lightly steamed Brussels sprouts each evening for 7 days prior to taking capsule containing 50 ng (5.4 nCi) [14C]-benzo[a]pyrene (BaP).
Cycle 3: Subjects will consume 300 mg DIM supplement ( 2 capsules of BioResponse DIM® 150) each evening for 7 days prior to taking capsule containing 50 ng (5.4 nCi) [14C]-benzo[a]pyrene (BaP). A 300 mg DIM dose will be co-administrated with the 50 ng BaP dose.
At least 3 weeks will pass between cycles as a washout period. Receives: Drug: [14C]-benzo[a]pyrene; Drug: Brussels sprouts before 50 ng dose; Drug: DIM supplement before 50 ng dose |
What is being measured
The primary outcome is the main question the study is designed to answer.
Peak Plasma Concentration of 14C-BaP Cmax
Determination of highest concentration of 14C-BaP in plasma. Blood samples collected at 0 (baseline), 0.25, 0.5, 1, 2, 3, 4, 8, 24, and 48 hour after dosing. All time points were used to determine Cmax.
Measured: 0-48 hours for each of 3 dosing cycles, with a washout period of 3 weeks between each dosing cycle
Secondary outcomes (3)
Time at Highest Plasma Concentration of 14C-BaP Tmax
Determination of time at which plasma concentration of 14C-BaP is highest. Blood samples collected at 0 (baseline), 0.25, 0.5, 1, 2, 3, 4, 8, 24, and 48 hour after dosing. All time points were used to determine Tmax.
Measured: 0-48 hours for each of 3 dosing cycles, with a washout period of 3 weeks between each dosing cycle
Area Under Plasma Concentration of 14C-BaP Versus Time Curve AUC
Integration of concentration of 14C-BaP in plasma over time. Blood samples collected at 0 (baseline), 0.25, 0.5, 1, 2, 3, 4, 8, 24, and 48 hour after dosing. All time points were used to determine AUC.
Measured: 0-48 hours for each of 3 dosing cycles, with a washout period of 3 weeks between each dosing cycle
Rate of Elimination of 14C-BaP (Half Life)
Determination of constants for rate of elimination of 14C-BaP from plasma. Blood samples collected at 0 (baseline), 0.25, 0.5, 1, 2, 3, 4, 8, 24, and 48 hour after dosing. All time points were used to determine half-life.
Measured: 0-48 hours for each of 3 dosing cycles, with a washout period of 3 weeks between each dosing cycle
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Jan 2019
- Study start24 Jan 2019
- Primary completion1 Jan 2024
- Study completion1 Feb 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Environmental ExposureStudies 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
- Early Phase 1
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 7 participants (actual)
Sponsor and investigators
- Lead sponsor
- Oregon State University
- Sponsor type
- University, hospital or other
- Collaborators
- National Institute of Environmental Health Sciences (NIEHS), Lawrence Livermore National Laboratory, Pacific Northwest National Laboratory
- Responsible party
- Principal investigator, David Williams, Oregon State University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03802721
- Sponsor's protocol ID
- LPI-8789
- Other IDs
- R01ES028600
- Status last verified
- Jun 2025
- First submitted
- 10 Jan 2019
- Last updated
- 22 Jun 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No: Deidentified samples sent to Lawrence Livermore National Laboratory Deidentified data sent to Pacific Northwest National Laboratory
Study at a glance
From the registry record, last updated by the sponsor on 22 Jun 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Pharmacokinetics of Benzo[a]Pyrene: Impact of Diet
- ClinicalTrials.gov ID
- NCT03802721
- Acronym / sponsor ID
- LPI-8789
- Conditions
- Environmental Exposure
- Keywords
- Benzo[a]pyrene, Accelerator Mass Spectrometry, Polycyclic Aromatic Hydrocarbons, cruciferous vegetable, Brussels sprouts, 3,3'-diindolylmethane, DIM, indole-3-carbinol
- Phase
- Early Phase 1
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 7 participants (actual)
- Lead sponsor
- Oregon State UniversityUniversity, hospital or other
- Collaborators
- National Institute of Environmental Health Sciences (NIEHS), Lawrence Livermore National Laboratory, Pacific Northwest National Laboratory
- Study start
- 24 Jan 2019 (actual)
- Primary completion
- 1 Jan 2024 (actual)
- Study completion
- 1 Feb 2024 (actual)
- First posted
- 14 Jan 2019 (actual)
- Results
- Posted 9 May 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Evaluation of the pharmacokinetics for [14C]-benzo[a]pyrene ([14C]-BaP) and metabolites in plasma and urine over 48 hours following a 50 ng dose (5.4 nCi) alone, following 7 days' consumption of Brussels sprouts, and following 7 days' consumption of a supplement containing 3,3'-diindolylmethane (DIM).
Detailed description
The pharmacokinetics for [14C]-BaP and metabolites will be assessed by UHLPC-Accelerator Mass Spectrometry (AMS, Lawrence Livermore National Laboratory) in plasma and urine collected over 48 hours following oral doses of 50 ng dose (5.4 nCi) alone, following 7 days' consumption of Brussels sprouts, and following 7 days' consumption of a supplement containing 3,3'-diindolylmethane (DIM).
The investigators hypothesize that pre-administration of Brussels sprouts or DIM will alter [14C]-BaP metabolism and increase the rate of elimination consistent with predictions based on a previously developed Physiologically-Based Pharmacokinetic (PBPK) model for BaP. Briefly, this hypothesis will be tested by dosing individuals with 50 ng [14C]-BaP alone and, following a 3-week washout period, ingestion of about 50 g Brussels sprouts or 300 mg of 3,3'-diindolylmethane (DIM) supplement for 7 days prior to the [14C]-BaP micro-dose. The impact of the supplement and the whole food will be assessed with respect to alterations in uptake from the GI tract, metabolism and rate of elimination. The consumption of cruciferous vegetables will be assessed at the beginning of the study by completion of a dietary questionnaire to examine typical eating patterns in the previous 3 months and by collection and extraction of blood and urine to assay for DIM by LC/ESI-MS/MS-SRM). In addition, for each phase, urine will be assayed for DIM as an estimate of crucifer or DIM supplement intake.
In preclinical and clinical studies, administration of Brussels sprouts or DIM impacts the activity of the same enzymes responsible for the phase 1 (CYP1A1 and CYP1B1) and phase 2 enzymes (GSTM1, UGT, SULT). Monitoring changes in β-estradiol metabolites will confirm the mechanism of alteration in the metabolic profile of [14C]-BaP.
Metabolite profiles and kinetics of elimination are predicted to be consistent with a BaP physiologically based pharmacokinetic (PBPK) model developed by Pacific Northwest National Laboratory (PNNL). A non-smoker, not exposed occupationally, receives 270-700 ng of BaP daily; about 95% dietary. The WHO has set an estimated safe daily lifetime (70 year/70 Kg individual, cancer endpoint) exposure to BaP of 42-350 ng. This protocol represents de minimus risk.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| 50 ng dose; Brussels sprouts before 50 ng dose; DIM supplement before 50 ng dose | Experimental | Drug: [14C]-benzo[a]pyrene, Drug: Brussels sprouts before 50 ng dose, Drug: DIM supplement before 50 ng doseCycle 1: Capsule containing 50 ng (5.4 nCi) [14C]-benzo[a]pyrene (BaP). Cycle 2: Subjects will consume 50 g (about 1/2 cup) of lightly steamed Brussels sprouts each evening for 7 days prior to taking capsule containing 50 ng (5.4 nCi) [14C]-benzo[a]pyrene (BaP). Cycle 3: Subjects will consume 300 mg DIM supplement ( 2 capsules of BioResponse DIM® 150) each evening for 7 days prior to taking capsule containing 50 ng (5.4 nCi) [14C]-benzo[a]pyrene (BaP). A 300 mg DIM dose will be co-administrated with the 50 ng BaP dose. At least 3 weeks will pass between cycles as a washout period. |
Who may qualify
- Ages
- 21 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Age 21-65 (inclusive)
- If female, must be post-menopausal or have had surgical sterilization to eliminate any possibility for fetal exposure
- Willing to defer blood donation for one month before, throughout, and one month after completion of study activities
- Willing to avoid consuming cruciferous vegetables, I3C or DIM supplements, smoked or cured meat or cheeses, or charcoal-grilled meats for 2 weeks prior to and during each study cycle (gas grilled foods acceptable)
- Health history review and physical assessment showing general good health, as determined by study physician. Acceptable physical exam may have been conducted as part of protocol 8233 or 8554 if subject has not had significant changes in health status.
Key exclusion criteria (8 listed)
- Smoker (tobacco or other substances) or use of smokeless tobacco in past 3 months or living with smoker
- Regular use of medications that affect gut motility or nutrient absorption (e.g. cholestyramine, sucralfate, orlistat, pro- or anti-motility agents)
- History of gastrointestinal surgery (e.g. bariatric surgery, cholecystectomy) or gastrointestinal disorder (Crohn's disease, celiac disease, IBS, or colitis)
- Current or history of kidney or liver disease
- Prior high-dose 14C exposure from medical tests. (micro-dose 14C exposure not exclusionary)
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 |
|---|---|---|
| [14C]-benzo[a]pyreneAlso: Carcinogenic PAH environmental pollutantOral micro-dose (50 ng) (5.4 nCi) | Drug | 50 ng dose; Brussels sprouts before 50 ng dose; DIM supplement before 50 ng dose |
| Brussels sprouts before 50 ng doseAlso: Brussels sprouts and carcinogenic PAHBrussels sprouts for 7 days before 50 ng (5.4 nCi) dose of BaP | Drug | 50 ng dose; Brussels sprouts before 50 ng dose; DIM supplement before 50 ng dose |
| DIM supplement before 50 ng doseAlso: Cruciferous vegetable supplement and carcinogenic PAHDIM supplement for 7 days before 50 ng (5.4 nCi) dose of BaP and coadministration with DIM supplement | Drug | 50 ng dose; Brussels sprouts before 50 ng dose; DIM supplement before 50 ng dose |
Primary outcome
Peak Plasma Concentration of 14C-BaP Cmax
Time frame: 0-48 hours for each of 3 dosing cycles, with a washout period of 3 weeks between each dosing cycle
Determination of highest concentration of 14C-BaP in plasma. Blood samples collected at 0 (baseline), 0.25, 0.5, 1, 2, 3, 4, 8, 24, and 48 hour after dosing. All time points were used to determine Cmax.
3 secondary outcomes
Time at Highest Plasma Concentration of 14C-BaP Tmax
Time frame: 0-48 hours for each of 3 dosing cycles, with a washout period of 3 weeks between each dosing cycle
Area Under Plasma Concentration of 14C-BaP Versus Time Curve AUC
Time frame: 0-48 hours for each of 3 dosing cycles, with a washout period of 3 weeks between each dosing cycle
Rate of Elimination of 14C-BaP (Half Life)
Time frame: 0-48 hours for each of 3 dosing cycles, with a washout period of 3 weeks between each dosing cycle
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 Jun 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: No. Deidentified samples sent to Lawrence Livermore National Laboratory Deidentified data sent to Pacific Northwest National Laboratory
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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.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Early Phase 1 study testing [14C]-benzo[a]pyrene, Brussels sprouts before 50 ng dose and DIM supplement before 50 ng dose in people with Environmental Exposure, run by Oregon State University at 1 site in United States.
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 5 inclusion and 8 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 22 Jun 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
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.
What does this phase mean?
Early Phase 1 (sometimes called Phase 0) studies give a very small amount of a treatment to a few people, mainly to see how the body handles it.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 9 May 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
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?
Peak Plasma Concentration of 14C-BaP Cmax (time frame: 0-48 hours for each of 3 dosing cycles, with a washout period of 3 weeks between each dosing cycle). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 22 Jun 2025.