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    <link:loc xlink:type="locator" xlink:label="loc_altri_VariacaoDePerimetro" xlink:href="051988-2025-12-31.xsd#altri_VariacaoDePerimetro"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_VariacaoDePerimetro" xlink:to="lab_altri_VariacaoDePerimetro" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_PagamentosDeAtividadesDeFinanciamento_019b4655-64b9-762a-9a61-b8c94e4ccc52_totalLabel_pt" xlink:label="lab_altri_PagamentosDeAtividadesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Pagamentos de atividades de financiamento</link:label>
    <link:label id="lab_altri_PagamentosDeAtividadesDeFinanciamento_label_pt" xlink:label="lab_altri_PagamentosDeAtividadesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Pagamentos de atividades de financiamento</link:label>
    <link:label id="lab_altri_PagamentosDeAtividadesDeFinanciamento_documentation_pt" xlink:label="lab_altri_PagamentosDeAtividadesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">As saídas de caixa referentes a atividades de financiamento.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_PagamentosDeAtividadesDeFinanciamento" xlink:href="051988-2025-12-31.xsd#altri_PagamentosDeAtividadesDeFinanciamento"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_PagamentosDeAtividadesDeFinanciamento" xlink:to="lab_altri_PagamentosDeAtividadesDeFinanciamento" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda_019b4655-64ba-7246-97a3-4b9fb2346bae_totalLabel_pt" xlink:label="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Outros resultados abrangentes de operações contínuas, itens que podem ser reclassificados para lucro líquido (perda)</link:label>
    <link:label id="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda_label_pt" xlink:label="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Outros resultados abrangentes de operações contínuas, itens que podem ser reclassificados para lucro líquido (perda)</link:label>
    <link:label id="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda_documentation_pt" xlink:label="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">Outros Resultados Abrangentes De Operações Contínuas, Itens Que Podem Ser Reclassificados Para Lucro Líquido (Perda)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda" xlink:href="051988-2025-12-31.xsd#altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda" xlink:to="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQuePodemSerReclassificadosParaLucroLiquidoPerda" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_PagamentosDeIncentivosReembolsaveis_label_pt" xlink:label="lab_altri_PagamentosDeIncentivosReembolsaveis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Pagamentos De Incentivos Reembolsaveis</link:label>
    <link:label id="lab_altri_PagamentosDeIncentivosReembolsaveis_documentation_pt" xlink:label="lab_altri_PagamentosDeIncentivosReembolsaveis" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">As saídas de caixa, classificadas como atividades de financiamento, referentes a pagamentos de incentivos reembolsáveis.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_PagamentosDeIncentivosReembolsaveis" xlink:href="051988-2025-12-31.xsd#altri_PagamentosDeIncentivosReembolsaveis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_PagamentosDeIncentivosReembolsaveis" xlink:to="lab_altri_PagamentosDeIncentivosReembolsaveis" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_EmprestimosBancariosCorrentes_label_pt" xlink:label="lab_altri_EmprestimosBancariosCorrentes" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Emprestimos Bancarios Correntes</link:label>
    <link:label id="lab_altri_EmprestimosBancariosCorrentes_documentation_pt" xlink:label="lab_altri_EmprestimosBancariosCorrentes" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">A quantia dos empréstimos bancários correntes e da parte corrente dos empréstimos bancários não correntes.</link:label>
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    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_EmprestimosBancariosCorrentes" xlink:to="lab_altri_EmprestimosBancariosCorrentes" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_ImpostoDeRendaRelacionadoAHedgesDeFluxoDeCaixaIncluidosEmOutrosResultadosAbrangentesDeOperacoesContinuas_label_pt" xlink:label="lab_altri_ImpostoDeRendaRelacionadoAHedgesDeFluxoDeCaixaIncluidosEmOutrosResultadosAbrangentesDeOperacoesContinuas" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Imposto de renda relacionado a hedges de fluxo de caixa incluídos em outros resultados abrangentes de operações contínuas</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_ImpostoDeRendaRelacionadoAHedgesDeFluxoDeCaixaIncluidosEmOutrosResultadosAbrangentesDeOperacoesContinuas" xlink:href="051988-2025-12-31.xsd#altri_ImpostoDeRendaRelacionadoAHedgesDeFluxoDeCaixaIncluidosEmOutrosResultadosAbrangentesDeOperacoesContinuas"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_ImpostoDeRendaRelacionadoAHedgesDeFluxoDeCaixaIncluidosEmOutrosResultadosAbrangentesDeOperacoesContinuas" xlink:to="lab_altri_ImpostoDeRendaRelacionadoAHedgesDeFluxoDeCaixaIncluidosEmOutrosResultadosAbrangentesDeOperacoesContinuas" xlink:type="arc" order="1"/>
    <link:label id="lab_ifrs-full_CashFlowsFromUsedInFinancingActivities_019b4655-64ba-7c76-b18b-97da76bee6c8_totalLabel_pt" xlink:label="lab_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Fluxos de caixa de (utilizados em) atividades de financiamento</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:href="https://xbrl.ifrs.org/taxonomy/2024-03-27/full_ifrs/full_ifrs-cor_2024-03-27.xsd#ifrs-full_CashFlowsFromUsedInFinancingActivities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:to="lab_ifrs-full_CashFlowsFromUsedInFinancingActivities" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_GanhosPerdasSobreDiferencasDeCambioNaConversaoDeOperacoesEstrangeirasDeOperacoesContinuasAntesDosImpostos_label_pt" xlink:label="lab_altri_GanhosPerdasSobreDiferencasDeCambioNaConversaoDeOperacoesEstrangeirasDeOperacoesContinuasAntesDosImpostos" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Ganhos (perdas) sobre diferenças de câmbio na conversão de operações estrangeiras de operações contínuas, antes dos impostos</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_GanhosPerdasSobreDiferencasDeCambioNaConversaoDeOperacoesEstrangeirasDeOperacoesContinuasAntesDosImpostos" xlink:href="051988-2025-12-31.xsd#altri_GanhosPerdasSobreDiferencasDeCambioNaConversaoDeOperacoesEstrangeirasDeOperacoesContinuasAntesDosImpostos"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_GanhosPerdasSobreDiferencasDeCambioNaConversaoDeOperacoesEstrangeirasDeOperacoesContinuasAntesDosImpostos" xlink:to="lab_altri_GanhosPerdasSobreDiferencasDeCambioNaConversaoDeOperacoesEstrangeirasDeOperacoesContinuasAntesDosImpostos" xlink:type="arc" order="1"/>
    <link:label id="lab_ifrs-full_CashFlowsFromUsedInInvestingActivities_019b4655-64b9-725b-ab61-d46a858a156b_totalLabel_pt" xlink:label="lab_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Fluxos de caixa de (utilizados em) atividades de investimento</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:href="https://xbrl.ifrs.org/taxonomy/2024-03-27/full_ifrs/full_ifrs-cor_2024-03-27.xsd#ifrs-full_CashFlowsFromUsedInInvestingActivities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:to="lab_ifrs-full_CashFlowsFromUsedInInvestingActivities" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_RecebimentosDeAtividadesDeFinanciamento_019b4655-64b9-78f4-9455-007b65d4c96d_totalLabel_pt" xlink:label="lab_altri_RecebimentosDeAtividadesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Recebimentos de atividades de financiamento</link:label>
    <link:label id="lab_altri_RecebimentosDeAtividadesDeFinanciamento_label_pt" xlink:label="lab_altri_RecebimentosDeAtividadesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Recebimentos De Atividades De Financiamento</link:label>
    <link:label id="lab_altri_RecebimentosDeAtividadesDeFinanciamento_documentation_pt" xlink:label="lab_altri_RecebimentosDeAtividadesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">As entradas de caixa, classificadas como atividades de financiamento.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_RecebimentosDeAtividadesDeFinanciamento" xlink:href="051988-2025-12-31.xsd#altri_RecebimentosDeAtividadesDeFinanciamento"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_RecebimentosDeAtividadesDeFinanciamento" xlink:to="lab_altri_RecebimentosDeAtividadesDeFinanciamento" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_IncentivosReembolsaveisCorrentes_label_pt" xlink:label="lab_altri_IncentivosReembolsaveisCorrentes" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Incentivos Reembolsaveis Correntes</link:label>
    <link:label id="lab_altri_IncentivosReembolsaveisCorrentes_documentation_pt" xlink:label="lab_altri_IncentivosReembolsaveisCorrentes" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">A quantia dos incentivos reembolsáveis correntes.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_IncentivosReembolsaveisCorrentes" xlink:href="051988-2025-12-31.xsd#altri_IncentivosReembolsaveisCorrentes"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_IncentivosReembolsaveisCorrentes" xlink:to="lab_altri_IncentivosReembolsaveisCorrentes" xlink:type="arc" order="1"/>
    <link:label id="lab_ifrs-full_InflowsOfCashFromInvestingActivities_019b4655-64ba-7dbd-b24b-59969d40f4d1_totalLabel_pt" xlink:label="lab_ifrs-full_InflowsOfCashFromInvestingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Entradas de caixa das atividades de investimento</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_InflowsOfCashFromInvestingActivities" xlink:href="https://xbrl.ifrs.org/taxonomy/2024-03-27/full_ifrs/full_ifrs-cor_2024-03-27.xsd#ifrs-full_InflowsOfCashFromInvestingActivities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ifrs-full_InflowsOfCashFromInvestingActivities" xlink:to="lab_ifrs-full_InflowsOfCashFromInvestingActivities" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_RecebimentosDeOutrasOperacoesDeFinanciamento_label_pt" xlink:label="lab_altri_RecebimentosDeOutrasOperacoesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Recebimentos De Outras Operacoes De Financiamento</link:label>
    <link:label id="lab_altri_RecebimentosDeOutrasOperacoesDeFinanciamento_documentation_pt" xlink:label="lab_altri_RecebimentosDeOutrasOperacoesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">As entradas de caixa, classificadas como atividades de financiamento, referentes a recebimentos de outras operações de financiamento.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_RecebimentosDeOutrasOperacoesDeFinanciamento" xlink:href="051988-2025-12-31.xsd#altri_RecebimentosDeOutrasOperacoesDeFinanciamento"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_RecebimentosDeOutrasOperacoesDeFinanciamento" xlink:to="lab_altri_RecebimentosDeOutrasOperacoesDeFinanciamento" xlink:type="arc" order="1"/>
    <link:label id="lab_ifrs-full_CashFlowsFromUsedInOperatingActivities_019b4655-64b9-7de6-8722-bf754bd91989_totalLabel_pt" xlink:label="lab_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Fluxos de caixa de (utilizados em) atividades de exploração</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:href="https://xbrl.ifrs.org/taxonomy/2024-03-27/full_ifrs/full_ifrs-cor_2024-03-27.xsd#ifrs-full_CashFlowsFromUsedInOperatingActivities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:to="lab_ifrs-full_CashFlowsFromUsedInOperatingActivities" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_OutrasReservasIncluindoLucrosRetidos_label_pt" xlink:label="lab_altri_OutrasReservasIncluindoLucrosRetidos" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Outras Reservas, Incluindo Lucros Retidos</link:label>
    <link:label id="lab_altri_OutrasReservasIncluindoLucrosRetidos_documentation_pt" xlink:label="lab_altri_OutrasReservasIncluindoLucrosRetidos" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">Outras Reservas, Incluindo Lucros Retidos</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_OutrasReservasIncluindoLucrosRetidos" xlink:href="051988-2025-12-31.xsd#altri_OutrasReservasIncluindoLucrosRetidos"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_OutrasReservasIncluindoLucrosRetidos" xlink:to="lab_altri_OutrasReservasIncluindoLucrosRetidos" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_ReceitasDeIncentivosReembolsaveis_label_pt" xlink:label="lab_altri_ReceitasDeIncentivosReembolsaveis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Receitas de incentivos reembolsáveis</link:label>
    <link:label id="lab_altri_ReceitasDeIncentivosReembolsaveis_documentation_pt" xlink:label="lab_altri_ReceitasDeIncentivosReembolsaveis" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">Receitas de incentivos reembolsáveis</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_ReceitasDeIncentivosReembolsaveis" xlink:href="051988-2025-12-31.xsd#altri_ReceitasDeIncentivosReembolsaveis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_ReceitasDeIncentivosReembolsaveis" xlink:to="lab_altri_ReceitasDeIncentivosReembolsaveis" xlink:type="arc" order="1"/>
    <link:label id="lab_ifrs-full_OutflowsOfCashFromInvestingActivities_019b4655-64ba-751f-81ad-5ee9d5d625e0_totalLabel_pt" xlink:label="lab_ifrs-full_OutflowsOfCashFromInvestingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Saídas de caixa de atividades de investimento</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_OutflowsOfCashFromInvestingActivities" xlink:href="https://xbrl.ifrs.org/taxonomy/2024-03-27/full_ifrs/full_ifrs-cor_2024-03-27.xsd#ifrs-full_OutflowsOfCashFromInvestingActivities"/>
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    <link:label id="lab_altri_OutrosPassivosCorrentes_documentation_pt" xlink:label="lab_altri_OutrosPassivosCorrentes" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">A quantia de outros passivos correntes, correspondentes a encargos a liquidar e subsídios ao investimento reconhecidos como rendimento diferido.</link:label>
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    <link:label id="lab_ifrs-full_CashAndCashEquivalentsIfDifferentFromStatementOfFinancialPosition_019b4655-64b9-7f69-a7e4-c9340adc71e0_periodStartLabel_pt" xlink:label="lab_ifrs-full_CashAndCashEquivalentsIfDifferentFromStatementOfFinancialPosition" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="pt">Caixa e equivalentes de caixa se diferentes da demonstração da posição financeira no início de periodo</link:label>
    <link:label id="lab_ifrs-full_CashAndCashEquivalentsIfDifferentFromStatementOfFinancialPosition_019b4655-64b9-7a7d-97ab-7fc3f48c3a0a_periodEndLabel_pt" xlink:label="lab_ifrs-full_CashAndCashEquivalentsIfDifferentFromStatementOfFinancialPosition" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="pt">Caixa e equivalentes de caixa se diferentes da demonstração da posição financeira no final de período</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_CashAndCashEquivalentsIfDifferentFromStatementOfFinancialPosition" xlink:href="https://xbrl.ifrs.org/taxonomy/2024-03-27/full_ifrs/full_ifrs-cor_2024-03-27.xsd#ifrs-full_CashAndCashEquivalentsIfDifferentFromStatementOfFinancialPosition"/>
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    <link:label id="lab_altri_PagamentosDeOutrasOperacoesDeFinanciamento_label_pt" xlink:label="lab_altri_PagamentosDeOutrasOperacoesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Pagamentos De Outras Operacoes De Financiamento</link:label>
    <link:label id="lab_altri_PagamentosDeOutrasOperacoesDeFinanciamento_documentation_pt" xlink:label="lab_altri_PagamentosDeOutrasOperacoesDeFinanciamento" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">As saídas de caixa, classificadas como atividades de financiamento, referentes a pagamentos de outras operações de financiamento.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_PagamentosDeOutrasOperacoesDeFinanciamento" xlink:href="051988-2025-12-31.xsd#altri_PagamentosDeOutrasOperacoesDeFinanciamento"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_PagamentosDeOutrasOperacoesDeFinanciamento" xlink:to="lab_altri_PagamentosDeOutrasOperacoesDeFinanciamento" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_GanhosPerdasEmHedgesDeFluxoDeCaixaDeOperacoesContinuasAntesDosImpostos_label_pt" xlink:label="lab_altri_GanhosPerdasEmHedgesDeFluxoDeCaixaDeOperacoesContinuasAntesDosImpostos" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Ganhos (perdas) em hedges de fluxo de caixa de operações contínuas, antes dos impostos</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_GanhosPerdasEmHedgesDeFluxoDeCaixaDeOperacoesContinuasAntesDosImpostos" xlink:href="051988-2025-12-31.xsd#altri_GanhosPerdasEmHedgesDeFluxoDeCaixaDeOperacoesContinuasAntesDosImpostos"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_GanhosPerdasEmHedgesDeFluxoDeCaixaDeOperacoesContinuasAntesDosImpostos" xlink:to="lab_altri_GanhosPerdasEmHedgesDeFluxoDeCaixaDeOperacoesContinuasAntesDosImpostos" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_OutrasReservasIncluindoLucrosRetidosMember_label_pt" xlink:label="lab_altri_OutrasReservasIncluindoLucrosRetidosMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Outras Reservas, Incluindo Lucros Retidos [Member]</link:label>
    <link:label id="lab_altri_OutrasReservasIncluindoLucrosRetidosMember_documentation_pt" xlink:label="lab_altri_OutrasReservasIncluindoLucrosRetidosMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">Outras Reservas, Incluindo Lucros Retidos</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_OutrasReservasIncluindoLucrosRetidosMember" xlink:href="051988-2025-12-31.xsd#altri_OutrasReservasIncluindoLucrosRetidosMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_OutrasReservasIncluindoLucrosRetidosMember" xlink:to="lab_altri_OutrasReservasIncluindoLucrosRetidosMember" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_IncentivosReembolsaveisNaoCorrentes_label_pt" xlink:label="lab_altri_IncentivosReembolsaveisNaoCorrentes" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Incentivos Reembolsaveis Nao Correntes</link:label>
    <link:label id="lab_altri_IncentivosReembolsaveisNaoCorrentes_documentation_pt" xlink:label="lab_altri_IncentivosReembolsaveisNaoCorrentes" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">A quantia de incentivos reembolsáveis não correntes.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_IncentivosReembolsaveisNaoCorrentes" xlink:href="051988-2025-12-31.xsd#altri_IncentivosReembolsaveisNaoCorrentes"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_IncentivosReembolsaveisNaoCorrentes" xlink:to="lab_altri_IncentivosReembolsaveisNaoCorrentes" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQueNaoSeraoReclassificadosParaOLucroPrejuizoLiquido_019b4655-64b9-7e9c-819b-63693418776d_totalLabel_pt" xlink:label="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQueNaoSeraoReclassificadosParaOLucroPrejuizoLiquido" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Outros Resultados Abrangentes De Operações Contínuas, Itens Que Não Serão Reclassificados Para O Lucro (Prejuízo) Líquido</link:label>
    <link:label id="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQueNaoSeraoReclassificadosParaOLucroPrejuizoLiquido_label_pt" xlink:label="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQueNaoSeraoReclassificadosParaOLucroPrejuizoLiquido" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Outros Resultados Abrangentes De Operações Contínuas, Itens Que Não Serão Reclassificados Para O Lucro (Prejuízo) Líquido</link:label>
    <link:label id="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQueNaoSeraoReclassificadosParaOLucroPrejuizoLiquido_documentation_pt" xlink:label="lab_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQueNaoSeraoReclassificadosParaOLucroPrejuizoLiquido" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">Outros Resultados Abrangentes De Operações Contínuas, Itens Que Não Serão Reclassificados Para O Lucro (Prejuízo) Líquido</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQueNaoSeraoReclassificadosParaOLucroPrejuizoLiquido" xlink:href="051988-2025-12-31.xsd#altri_OutrosResultadosAbrangentesDeOperacoesContinuasItensQueNaoSeraoReclassificadosParaOLucroPrejuizoLiquido"/>
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    <link:label id="lab_altri_EmprestimosBancariosNaoCorrentes_label_pt" xlink:label="lab_altri_EmprestimosBancariosNaoCorrentes" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Emprestimos Bancarios Nao Correntes</link:label>
    <link:label id="lab_altri_EmprestimosBancariosNaoCorrentes_documentation_pt" xlink:label="lab_altri_EmprestimosBancariosNaoCorrentes" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">A parte não corrente dos empréstimos bancários não correntes.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_EmprestimosBancariosNaoCorrentes" xlink:href="051988-2025-12-31.xsd#altri_EmprestimosBancariosNaoCorrentes"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_EmprestimosBancariosNaoCorrentes" xlink:to="lab_altri_EmprestimosBancariosNaoCorrentes" xlink:type="arc" order="1"/>
    <link:label id="lab_altri_ProvisoesEPerdasPorImparidade_label_pt" xlink:label="lab_altri_ProvisoesEPerdasPorImparidade" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="pt">Provisoes E Perdas Por Imparidade</link:label>
    <link:label id="lab_altri_ProvisoesEPerdasPorImparidade_documentation_pt" xlink:label="lab_altri_ProvisoesEPerdasPorImparidade" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="pt">A quantia de reforços e reversões do exercício, de provisões e perdas por imparidade.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_altri_ProvisoesEPerdasPorImparidade" xlink:href="051988-2025-12-31.xsd#altri_ProvisoesEPerdasPorImparidade"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_altri_ProvisoesEPerdasPorImparidade" xlink:to="lab_altri_ProvisoesEPerdasPorImparidade" xlink:type="arc" order="1"/>
    <link:label id="lab_ifrs-full_IncreaseDecreaseInCashAndCashEquivalentsBeforeEffectOfExchangeRateChanges_019b4655-64ba-7377-ae49-18dcf8d15c19_totalLabel_pt" xlink:label="lab_ifrs-full_IncreaseDecreaseInCashAndCashEquivalentsBeforeEffectOfExchangeRateChanges" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="pt">Aumento (diminuição) de caixa e equivalentes de caixa antes do efeito das variações das taxas de câmbio</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_ifrs-full_IncreaseDecreaseInCashAndCashEquivalentsBeforeEffectOfExchangeRateChanges" xlink:href="https://xbrl.ifrs.org/taxonomy/2024-03-27/full_ifrs/full_ifrs-cor_2024-03-27.xsd#ifrs-full_IncreaseDecreaseInCashAndCashEquivalentsBeforeEffectOfExchangeRateChanges"/>
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