﻿<?xml version="1.0" encoding="utf-8"?>
<Return xmlns="http://www.irs.gov/efile" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" returnVersion="2025v4.0">
  <ReturnHeader binaryAttachmentCnt="0">
    <ReturnTs>2026-03-20T14:44:04+00:00</ReturnTs>
    <TaxPeriodEndDt>2025-12-31</TaxPeriodEndDt>
    <PreparerFirmGrp>
      <PreparerFirmEIN>440160260</PreparerFirmEIN>
      <PreparerFirmName>
        <BusinessNameLine1Txt>Forvis Mazars LLP</BusinessNameLine1Txt>
      </PreparerFirmName>
      <PreparerUSAddress>
        <AddressLine1Txt>One Oak Plaza Suite 300</AddressLine1Txt>
        <CityNm>Asheville</CityNm>
        <StateAbbreviationCd>NC</StateAbbreviationCd>
        <ZIPCd>28801</ZIPCd>
      </PreparerUSAddress>
    </PreparerFirmGrp>
    <ReturnTypeCd>990EZ</ReturnTypeCd>
    <TaxPeriodBeginDt>2025-01-01</TaxPeriodBeginDt>
    <Filer>
      <EIN>311013937</EIN>
      <BusinessName>
        <BusinessNameLine1Txt>Developmental Neurotoxicology Society (DNTS)</BusinessNameLine1Txt>
      </BusinessName>
      <BusinessNameControlTxt>DEVE</BusinessNameControlTxt>
      <PhoneNum>4103404629</PhoneNum>
      <USAddress>
        <AddressLine1Txt>2624 Malin Dr</AddressLine1Txt>
        <CityNm>Tallahassee</CityNm>
        <StateAbbreviationCd>FL</StateAbbreviationCd>
        <ZIPCd>32309</ZIPCd>
      </USAddress>
    </Filer>
    <BusinessOfficerGrp>
      <PersonNm>Devon Graham</PersonNm>
      <PersonTitleTxt>Treasurer</PersonTitleTxt>
      <SignatureDt>2026-03-20</SignatureDt>
      <DiscussWithPaidPreparerInd>true</DiscussWithPaidPreparerInd>
    </BusinessOfficerGrp>
    <PreparerPersonGrp>
      <PreparerPersonNm>Amy Bibby</PreparerPersonNm>
      <PTIN>P00445891</PTIN>
      <PhoneNum>8282542254</PhoneNum>
      <PreparationDt>2026-03-20</PreparationDt>
    </PreparerPersonGrp>
    <TaxYr>2025</TaxYr>
    <BuildTS>2025-03-06 01:10:19Z</BuildTS>
  </ReturnHeader>
  <ReturnData documentCnt="4">
    <IRS990EZ documentId="IRS990EZ" softwareId="25022866" softwareVersionNum="2025v4.0">
      <MethodOfAccountingCashInd>X</MethodOfAccountingCashInd>
      <WebsiteAddressTxt>www.DNTSHOME.org</WebsiteAddressTxt>
      <Organization501c3Ind referenceDocumentId="IRS990ScheduleA">X</Organization501c3Ind>
      <TypeOfOrganizationCorpInd>X</TypeOfOrganizationCorpInd>
      <GrossReceiptsAmt>30600</GrossReceiptsAmt>
      <InfoInScheduleOPartIInd>X</InfoInScheduleOPartIInd>
      <ContributionsGiftsGrantsEtcAmt>10635</ContributionsGiftsGrantsEtcAmt>
      <MembershipDuesAmt>17791</MembershipDuesAmt>
      <InvestmentIncomeAmt>2174</InvestmentIncomeAmt>
      <GainOrLossFromSaleOfAssetsAmt>0</GainOrLossFromSaleOfAssetsAmt>
      <SpecialEventsNetIncomeLossAmt>0</SpecialEventsNetIncomeLossAmt>
      <GrossProfitLossSlsOfInvntryAmt>0</GrossProfitLossSlsOfInvntryAmt>
      <OtherRevenueTotalAmt>0</OtherRevenueTotalAmt>
      <TotalRevenueAmt>30600</TotalRevenueAmt>
      <GrantsAndSimilarAmountsPaidAmt>0</GrantsAndSimilarAmountsPaidAmt>
      <OtherExpensesTotalAmt>47129</OtherExpensesTotalAmt>
      <TotalExpensesAmt>47129</TotalExpensesAmt>
      <ExcessOrDeficitForYearAmt>-16529</ExcessOrDeficitForYearAmt>
      <NetAssetsOrFundBalancesBOYAmt>109179</NetAssetsOrFundBalancesBOYAmt>
      <OtherChangesInNetAssetsAmt>7800</OtherChangesInNetAssetsAmt>
      <NetAssetsOrFundBalancesEOYAmt>100450</NetAssetsOrFundBalancesEOYAmt>
      <CashSavingsAndInvestmentsGrp>
        <BOYAmt>109179</BOYAmt>
        <EOYAmt>100450</EOYAmt>
      </CashSavingsAndInvestmentsGrp>
      <LandAndBuildingsGrp>
        <BOYAmt>0</BOYAmt>
        <EOYAmt>0</EOYAmt>
      </LandAndBuildingsGrp>
      <OtherAssetsTotalDetail>
        <BOYAmt>0</BOYAmt>
        <EOYAmt>0</EOYAmt>
      </OtherAssetsTotalDetail>
      <Form990TotalAssetsGrp>
        <BOYAmt>109179</BOYAmt>
        <EOYAmt>100450</EOYAmt>
      </Form990TotalAssetsGrp>
      <SumOfTotalLiabilitiesGrp>
        <BOYAmt>0</BOYAmt>
        <EOYAmt>0</EOYAmt>
      </SumOfTotalLiabilitiesGrp>
      <NetAssetsOrFundBalancesGrp>
        <BOYAmt>109179</BOYAmt>
        <EOYAmt>100450</EOYAmt>
      </NetAssetsOrFundBalancesGrp>
      <InfoInScheduleOPartIIIInd>X</InfoInScheduleOPartIIIInd>
      <PrimaryExemptPurposeTxt>the organization has one purpose which is an annual meeting of scientists for educational purposes. this annual meeting has approximately 100 member attendees. a monthly publication is sent to all members. a website is provided to give members access to information and to inform the public.</PrimaryExemptPurposeTxt>
      <ProgramSrvcAccomplishmentGrp>
        <DescriptionProgramSrvcAccomTxt>The annual meeting has approximately 100 member attendees. a monthly publication is sent to all members. a website is provided to give members access to information and to inform the public.</DescriptionProgramSrvcAccomTxt>
        <GrantsAndAllocationsAmt>0</GrantsAndAllocationsAmt>
        <ProgramServiceExpensesAmt>47129</ProgramServiceExpensesAmt>
      </ProgramSrvcAccomplishmentGrp>
      <TotalProgramServiceExpensesAmt>47129</TotalProgramServiceExpensesAmt>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Kim Yolton</PersonNm>
        <TitleTxt>President</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>20.000</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Devon Graham</PersonNm>
        <TitleTxt>Treasurer</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>3.000</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Megan Woodbury</PersonNm>
        <TitleTxt>Secretary</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>3.000</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Natacha DeGenna</PersonNm>
        <TitleTxt>President-Elect</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>2.000</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Lori Driscoll</PersonNm>
        <TitleTxt>Council</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>2.000</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Gregg Stanwood</PersonNm>
        <TitleTxt>Council</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>2.000</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Chris Curran</PersonNm>
        <TitleTxt>Council</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>2.000</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Stephanie Godleski</PersonNm>
        <TitleTxt>Council</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>2.000</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Tom Burbacher</PersonNm>
        <TitleTxt>Council</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>2.000</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
        <ExpenseAccountOtherAllwncAmt>0</ExpenseAccountOtherAllwncAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <ActivitiesNotPreviouslyRptInd>false</ActivitiesNotPreviouslyRptInd>
      <ChgMadeToOrgnzngDocNotRptInd>false</ChgMadeToOrgnzngDocNotRptInd>
      <OrganizationHadUBIInd>false</OrganizationHadUBIInd>
      <SubjectToProxyTaxInd>false</SubjectToProxyTaxInd>
      <OrganizationDissolvedEtcInd>false</OrganizationDissolvedEtcInd>
      <DirectIndirectPltclExpendAmt>0</DirectIndirectPltclExpendAmt>
      <Form1120PolFiledInd>false</Form1120PolFiledInd>
      <MadeLoansToFromOfficersInd>false</MadeLoansToFromOfficersInd>
      <LoansToFromOfficersAmt>0</LoansToFromOfficersAmt>
      <TaxImposedUnderIRC4911Amt>0</TaxImposedUnderIRC4911Amt>
      <TaxImposedUnderIRC4912Amt>0</TaxImposedUnderIRC4912Amt>
      <TaxImposedUnderIRC4955Amt>0</TaxImposedUnderIRC4955Amt>
      <EngagedInExcessBenefitTransInd>false</EngagedInExcessBenefitTransInd>
      <ProhibitedTaxShelterTransInd>false</ProhibitedTaxShelterTransInd>
      <BooksInCareOfDetail>
        <BusinessName>
          <BusinessNameLine1Txt>Devon Graham</BusinessNameLine1Txt>
        </BusinessName>
        <USAddress>
          <AddressLine1Txt>2624 Malin Dr</AddressLine1Txt>
          <CityNm>Tallahassee</CityNm>
          <StateAbbreviationCd>FL</StateAbbreviationCd>
          <ZIPCd>32309</ZIPCd>
        </USAddress>
        <PhoneNum>4103404629</PhoneNum>
      </BooksInCareOfDetail>
      <ForeignFinancialAccountInd>false</ForeignFinancialAccountInd>
      <ForeignOfficeInd>false</ForeignOfficeInd>
      <DonorAdvisedFndsInd>false</DonorAdvisedFndsInd>
      <OperateHospitalInd>false</OperateHospitalInd>
      <TanningServicesProvidedInd>false</TanningServicesProvidedInd>
      <RelatedOrganizationCtrlEntInd>false</RelatedOrganizationCtrlEntInd>
      <TransactionWithControlEntInd>false</TransactionWithControlEntInd>
      <PoliticalCampaignActyInd>false</PoliticalCampaignActyInd>
      <LobbyingActivitiesInd>false</LobbyingActivitiesInd>
      <SchoolOperatingInd>false</SchoolOperatingInd>
      <TrnsfrExmptNonChrtblRltdOrgInd>false</TrnsfrExmptNonChrtblRltdOrgInd>
      <OtherEmployeePaidOver100kCnt>0</OtherEmployeePaidOver100kCnt>
      <FiledScheduleAInd>true</FiledScheduleAInd>
    </IRS990EZ>
    <IRS990ScheduleA documentId="IRS990ScheduleA" softwareId="25022866" softwareVersionNum="2025v4.0">
      <PublicOrganization170Ind>X</PublicOrganization170Ind>
      <GiftsGrantsContriRcvd170Grp>
        <CurrentTaxYearMinus4YearsAmt>20173</CurrentTaxYearMinus4YearsAmt>
        <CurrentTaxYearMinus3YearsAmt>42884</CurrentTaxYearMinus3YearsAmt>
        <CurrentTaxYearMinus2YearsAmt>35506</CurrentTaxYearMinus2YearsAmt>
        <CurrentTaxYearMinus1YearAmt>28774</CurrentTaxYearMinus1YearAmt>
        <CurrentTaxYearAmt>28426</CurrentTaxYearAmt>
        <TotalAmt>155763</TotalAmt>
      </GiftsGrantsContriRcvd170Grp>
      <TaxRevLeviedOrgnztnlBnft170Grp>
        <CurrentTaxYearAmt>0</CurrentTaxYearAmt>
        <TotalAmt>0</TotalAmt>
      </TaxRevLeviedOrgnztnlBnft170Grp>
      <GovtFurnSrvcFcltsVl170Grp>
        <CurrentTaxYearAmt>0</CurrentTaxYearAmt>
        <TotalAmt>0</TotalAmt>
      </GovtFurnSrvcFcltsVl170Grp>
      <TotalCalendarYear170Grp>
        <CurrentTaxYearMinus4YearsAmt>20173</CurrentTaxYearMinus4YearsAmt>
        <CurrentTaxYearMinus3YearsAmt>42884</CurrentTaxYearMinus3YearsAmt>
        <CurrentTaxYearMinus2YearsAmt>35506</CurrentTaxYearMinus2YearsAmt>
        <CurrentTaxYearMinus1YearAmt>28774</CurrentTaxYearMinus1YearAmt>
        <CurrentTaxYearAmt>28426</CurrentTaxYearAmt>
        <TotalAmt>155763</TotalAmt>
      </TotalCalendarYear170Grp>
      <SubstantialContributorsTotAmt>21738</SubstantialContributorsTotAmt>
      <PublicSupportTotal170Amt>134025</PublicSupportTotal170Amt>
      <GrossInvestmentIncome170Grp>
        <CurrentTaxYearMinus4YearsAmt>385</CurrentTaxYearMinus4YearsAmt>
        <CurrentTaxYearMinus3YearsAmt>474</CurrentTaxYearMinus3YearsAmt>
        <CurrentTaxYearMinus2YearsAmt>942</CurrentTaxYearMinus2YearsAmt>
        <CurrentTaxYearMinus1YearAmt>3373</CurrentTaxYearMinus1YearAmt>
        <CurrentTaxYearAmt>2174</CurrentTaxYearAmt>
        <TotalAmt>7348</TotalAmt>
      </GrossInvestmentIncome170Grp>
      <UnrelatedBusinessNetIncm170Grp>
        <CurrentTaxYearAmt>0</CurrentTaxYearAmt>
        <TotalAmt>0</TotalAmt>
      </UnrelatedBusinessNetIncm170Grp>
      <OtherIncome170Grp>
        <CurrentTaxYearMinus4YearsAmt>0</CurrentTaxYearMinus4YearsAmt>
        <CurrentTaxYearMinus3YearsAmt>0</CurrentTaxYearMinus3YearsAmt>
        <CurrentTaxYearMinus2YearsAmt>0</CurrentTaxYearMinus2YearsAmt>
        <CurrentTaxYearMinus1YearAmt>0</CurrentTaxYearMinus1YearAmt>
        <CurrentTaxYearAmt>0</CurrentTaxYearAmt>
        <TotalAmt>0</TotalAmt>
      </OtherIncome170Grp>
      <TotalSupportAmt>163111</TotalSupportAmt>
      <GrossReceiptsRltdActivitiesAmt>0</GrossReceiptsRltdActivitiesAmt>
      <PublicSupportCY170Pct>0.82168</PublicSupportCY170Pct>
      <PublicSupportPY170Pct>0.83967</PublicSupportPY170Pct>
      <ThirtyThrPctSuprtTestsCY170Ind>X</ThirtyThrPctSuprtTestsCY170Ind>
    </IRS990ScheduleA>
    <IRS990ScheduleB documentId="IRS990ScheduleB" softwareId="25022866" softwareVersionNum="2025v4.0">
      <ContributorInformationGrp>
        <ContributorNum>RESTRICTED</ContributorNum>
        <ContributorBusinessName>
          <BusinessNameLine1>RESTRICTED</BusinessNameLine1>
        </ContributorBusinessName>
        <ContributorUSAddress>
          <AddressLine1>RESTRICTED</AddressLine1>
          <AddressLine2>RESTRICTED</AddressLine2>
          <City>RESTRICTED</City>
          <State>RESTRICTED</State>
          <ZIPCode>RESTRICTED</ZIPCode>
        </ContributorUSAddress>
        <TotalContributionsAmt>RESTRICTED</TotalContributionsAmt>
      </ContributorInformationGrp>
    </IRS990ScheduleB>
    <IRS990ScheduleO documentId="IRS990ScheduleO" softwareId="25022866" softwareVersionNum="2025v4.0">
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990-EZ, Part I, Line 16 Other Expenses</FormAndLineReferenceDesc>
        <ExplanationTxt>Conferences, Conventions, &amp; Meetings - 29385; Accounting Fees - 7980; Business Expense - 2459; Meeting Awards - 7305;</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990-EZ, Part I, Line 20 Net Assets Change</FormAndLineReferenceDesc>
        <ExplanationTxt>Unrealized Gain / Loss - 7800;</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990-EZ, Part III, Exempt Purpose PRIMARY EXEMPT PURPOSE</FormAndLineReferenceDesc>
        <ExplanationTxt>the organization has one purpose which is an annual meeting of scientists for educational purposes. this annual meeting has approximately 100 member attendees. a monthly publication is sent to all members. a website is provided to give members access to information and to inform the public.</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990EZ, Part III, Line 28 DESCRIPTION OF OTHER PROGRAM SERVICES</FormAndLineReferenceDesc>
        <ExplanationTxt>The annual meeting has approximately 100 member attendees. a monthly publication is sent to all members. a website is provided to give members access to information and to inform the public.</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleO>
  </ReturnData>
</Return>