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B1 adjective #4,000 most common 10 min read

tóxico

Top 4,000

Practice it Examples Notes & Tips tóxico in 30 Seconds

Explanation tóxico in your Level:

At the A1 level, you should learn 'tóxico' as a simple word to describe things that are very bad for your health or dangerous. Think of it as 'dangerous' (perigoso) but specifically for things you shouldn't eat, drink, or breathe. You will mostly see this on signs or labels. For example, if you see a bottle with a skull, it is 'tóxico'. At this stage, don't worry about the psychological meanings. Just remember that it ends in 'o' for masculine things (o lixo tóxico) and 'a' for feminine things (a comida tóxica). It sounds a bit like the English word 'toxic', which makes it easy to remember. Focus on simple sentences like 'Isso é tóxico' (This is toxic).

At the A2 level, you can start using 'tóxico' to describe environmental issues and basic health concepts. You might talk about 'fumaça tóxica' (toxic smoke) from cars or factories. You are also beginning to see the word in more varied contexts, such as describing a very bad environment. You should practice the plural forms: 'produtos tóxicos' (toxic products). This is a good time to distinguish it from 'venenoso' (poisonous like a snake). You might say 'O produto de limpeza é tóxico' (The cleaning product is toxic). You should also be aware of the noun 'toxina' (toxin).

At the B1 level, you should master the metaphorical use of 'tóxico'. This is where you describe 'relacionamentos tóxicos' (toxic relationships) or 'pessoas tóxicas' (toxic people). You should be able to discuss why something is toxic and use the word in more complex sentences involving feelings and social dynamics. You will hear this word often in Brazilian soap operas (novelas) or Portuguese news. You should also understand related words like 'intoxicação' (poisoning), especially 'intoxicação alimentar' (food poisoning). You can now use 'tóxico' to express opinions about social environments, such as 'Eu saí daquele emprego porque o ambiente era tóxico' (I left that job because the environment was toxic).

At the B2 level, you should be comfortable using 'tóxico' in professional and academic discussions. You will encounter it in terms like 'resíduos tóxicos' (toxic waste) in environmental debates or 'masculinidade tóxica' (toxic masculinity) in sociological contexts. You should be able to explain the difference between 'tóxico' and 'nocivo' (harmful) or 'insalubre' (unhealthy/hazardous). Your vocabulary should include the noun 'toxicidade' (toxicity) and you should be able to discuss the 'níveis de toxicidade' (toxicity levels) of a substance. You can also use it to describe abstract concepts like 'positividade tóxica' (toxic positivity).

At the C1 level, you use 'tóxico' and its derivatives with precision and nuance. You understand its legal implications, such as 'crimes ambientais' involving 'substâncias tóxicas'. You can participate in deep debates about the 'toxicidade sistêmica' in certain institutions. You are familiar with technical terms like 'neurotóxico' or 'citotóxico' in medical or scientific contexts. You can use the word ironically or in high-level literary analysis. You also understand the historical etymology and how the word has shifted in Portuguese society compared to other Lusophone cultures.

At the C2 level, you have a native-like grasp of 'tóxico'. You can use it in any register, from highly technical scientific papers to the most informal street slang. You understand the subtle connotations it carries in different Portuguese-speaking countries (e.g., how it might be used in Angola vs. Portugal vs. Brazil). You can use it to construct complex metaphors and navigate the most delicate social or political discussions where the term might be used to label movements or ideologies. You are also aware of the word's role in contemporary 'culture wars' and can use it or critique its use with complete fluency.

Practice it Examples Notes & Tips

tóxico in 30 Seconds

Tóxico is an adjective meaning poisonous or harmful, used for both physical substances and negative social behaviors.
It must agree in gender and number with the noun it modifies: tóxico, tóxica, tóxicos, tóxicas.
In modern Portuguese, it is extremely common to describe 'relacionamentos tóxicos' (toxic relationships).
Be careful not to confuse it with 'venenoso', which is specifically for natural poisons like snake venom.

The Portuguese word tóxico is a versatile adjective that has evolved significantly in its usage over the last few decades. At its most fundamental level, it describes substances that are chemically harmful, poisonous, or capable of causing physiological damage to a living organism. When you walk through a factory or look at a cleaning product in Brazil or Portugal, you might see a skull and crossbones symbol accompanied by the word tóxico. This literal application covers everything from industrial waste to carbon monoxide. However, the modern speaker is just as likely to use this word in a psychological or social context. In contemporary Portuguese, tóxico is the primary descriptor for harmful human behaviors and environments. It describes relationships, workplaces, or personality traits that drain energy, cause emotional distress, or undermine a person's well-being. This metaphorical shift mirrors the English usage of 'toxic,' making it a high-frequency cognate for English learners, though one must be careful with gender and number agreement.

Literal Chemistry: Refers to substances like pesticides, heavy metals, or hazardous fumes that pose a direct threat to biological health. In this context, it is often found in scientific reports or safety labels.

Cuidado, este produto químico é altamente tóxico se for ingerido.

Social Psychology: Describes individuals or groups whose behavior is manipulative, negative, or emotionally damaging. Phrases like 'relacionamento tóxico' (toxic relationship) are extremely common in modern Portuguese discourse.

Ela finalmente percebeu que estava em um ambiente de trabalho tóxico.

Furthermore, the word is used in environmental discussions to describe pollution. 'Resíduos tóxicos' (toxic waste) is a frequent term in news regarding sustainability. In the digital age, you will also hear about 'toxicidade' (toxicity) in online gaming communities or social media comment sections, referring to harassment and negativity. Understanding this word requires recognizing that it spans from the tangible, measurable world of science to the abstract, felt world of human emotion.

O descarte de materiais tóxicos no rio causou um desastre ambiental.

Cultural Nuance: In Brazil, the term 'tóxico' is sometimes used in slang to refer to drugs in general, though this is informal and context-dependent. Usually, it maintains its standard meaning of harmful or poisonous.

Precisamos nos afastar de pessoas tóxicas para preservar nossa saúde mental.

Using tóxico correctly in Portuguese involves mastering adjective-noun agreement and understanding its placement. As an adjective, it typically follows the noun it modifies. For example, 'toxic gas' becomes 'gás tóxico'. If you are describing multiple toxic items, the adjective becomes plural: 'gases tóxicos'. When the noun is feminine, the ending changes to '-a': 'uma amizade tóxica' (a toxic friendship). This grammatical flexibility is essential for sounding natural in Portuguese. In most cases, tóxico is used with the verb ser (to be - permanent quality) rather than estar (to be - temporary state), because toxicity is usually seen as an inherent property of a substance or a deep-seated trait of a person.

Masculine Singular: Used for masculine nouns like 'ar' (air), 'lixo' (trash), or 'comportamento' (behavior).

O mercúrio é um metal tóxico que afeta o sistema nervoso.

Feminine Singular: Used for feminine nouns like 'substância' (substance), 'planta' (plant), or 'atitude' (attitude).

Aquela planta é tóxica para animais de estimação.

In academic and technical writing, you might see tóxico appearing in compound terms like 'agrotóxico' (pesticide/agro-toxic). In common speech, however, the word is increasingly used as a standalone descriptor for social fatigue. If someone says 'O clima na festa estava tóxico' (The vibe at the party was toxic), they are using a figurative extension to describe a negative atmosphere. It is also important to note that 'tóxico' can function as a noun in very specific medical contexts (referring to a toxic agent), but this is rare compared to its adjective use.

Muitos cosméticos antigos continham ingredientes tóxicos.

Feminine Plural: Used for plural feminine nouns like 'algas' (algae) or 'relações' (relations).

As emissões tóxicas das fábricas precisam ser controladas.

You will encounter the word tóxico in a variety of settings, ranging from the evening news to casual conversations over coffee. In the news, it frequently appears during environmental reports or health segments. For instance, when a city suffers from high levels of pollution, journalists will speak of 'nuvens de fumaça tóxica' (clouds of toxic smoke) or 'níveis tóxicos de poluição'. If there is a spill in a river, the focus will be on 'resíduos tóxicos' and their impact on local wildlife. In these contexts, the word carries a heavy, serious weight, signaling immediate physical danger. It is also a staple in Brazilian and Portuguese workplace culture discussions, where the term 'liderança tóxica' (toxic leadership) is used to describe bosses who create stressful environments.

Workplace & Professional Life: Used to describe corporate cultures that prioritize profit over employee well-being, often leading to burnout.

O RH recebeu denúncias sobre um gerente com comportamento tóxico.

Social Media & Internet: Common in discussions about 'cancel culture' and online harassment. Users often complain about 'comentários tóxicos' on their posts.

Eu decidi sair do Twitter porque a rede ficou muito tóxica.

Pop culture, including podcasts and self-help books, has embraced 'tóxico' as a keyword. You will see titles like 'Como identificar um relacionamento tóxico' (How to identify a toxic relationship) in every bookstore from Lisbon to São Paulo. In the world of sports, fans might describe a 'vestiário tóxico' (toxic locker room) when a team is performing poorly due to internal conflicts. Even in schools, teachers and parents discuss 'masculinidade tóxica' (toxic masculinity) as part of modern social education. Because it covers both physical and emotional harm, it has become one of the most useful adjectives for describing anything that is 'bad for you' in a profound way.

O documentário explora os efeitos tóxicos do plástico nos oceanos.

Health and Wellness: Used in the 'detox' (destoxificação) trend, where people try to remove 'toxinas' (toxins) from their bodies.

Muitas dietas prometem eliminar o excesso tóxico do organismo.

One of the most frequent mistakes English speakers make when using tóxico is failing to distinguish it from venenoso. While in English 'toxic' and 'poisonous' are often used interchangeably, Portuguese tends to be more specific. Venenoso is primarily used for biological organisms that produce venom, like snakes (cobras venenosas), spiders (aranhas venenosas), or certain plants. Tóxico is a broader term that includes chemical substances, pollution, and metaphorical harm. If you say a snake is 'tóxica', a native speaker will understand you, but 'venenosa' is the standard and more natural choice. Another mistake is forgetting gender agreement. Because 'tóxico' ends in 'o', many students default to this form even when describing feminine nouns like 'pessoa' (person) or 'relação' (relationship).

Agreement Errors: Saying 'uma relação tóxico' instead of 'uma relação tóxica'. Adjectives in Portuguese must match the gender of the noun.

Errado: A poluição é tóxico. Correto: A poluição é tóxica.

Confusion with 'Venenoso': Using 'tóxico' for a snake or a scorpion when 'venenoso' (or 'peçonhento' for animals that inject venom) is more appropriate.

Cuidado com essa cobra, ela é venenosa (Better than tóxica).

Another subtle mistake involves the pronunciation of the 'x'. In Portuguese, 'x' can represent four different sounds: /sh/, /s/, /z/, or /ks/. In tóxico, it is always the /ks/ sound. Some learners mistakenly pronounce it as 'tó-shico' (like the Portuguese word 'lixo'), which sounds incorrect to native ears. Additionally, be careful not to overuse the word in its metaphorical sense. While common, calling every minor disagreement 'tóxico' can sound exaggerated or like you are using too much 'internet slang'. Use synonyms like 'desagradável' (unpleasant) or 'complicado' (complicated) for milder situations.

A fumaça dos carros pode ser tóxica em ambientes fechados.

False Cognate Risks: While 'toxic' and 'tóxico' are mostly synonyms, the word 'intoxicação' in Portuguese often refers to food poisoning (intoxicação alimentar), which is much more common than the English 'intoxication' (which usually implies being drunk).

Ele teve uma intoxicação alimentar, não foi nada tóxico no sentido químico.

Depending on the context, you might want to use a more specific word than tóxico. If you are discussing health and safety, nocivo (harmful) or prejudicial (detrimental) are excellent alternatives. For environmental issues, poluente (pollutant) might be more precise. If you are describing a person who is difficult but perhaps not 'toxic' in the clinical sense, words like difícil (difficult) or negativo (negative) work well. Understanding these nuances will help you sound more like a native speaker and less like someone who is just translating English concepts directly into Portuguese.

Tóxico vs. Venenoso: Tóxico: General harmful substances, chemicals, or behaviors.
Venenoso: Specifically for poisons found in nature (plants/animals) or intended to kill via ingestion/injection.

O produto é tóxico, mas a picada da aranha é venenosa.

Tóxico vs. Nocivo: Tóxico: Implies a level of poison or deep harm.
Nocivo: Simply means harmful or injurious; it's a bit broader and can apply to habits (fumar é nocivo).

O excesso de açúcar é nocivo à saúde, mas não é necessariamente tóxico.

Another word to consider is insalubre. This is a very important word in Brazilian labor law. While 'tóxico' describes the substance, 'insalubre' describes the *condition* of working in a place that is harmful to health. If you work with toxic chemicals, your workplace is 'insalubre'. This distinction is crucial for anyone working in Brazil. For metaphorical toxicity, you can also use abusivo (abusive), which is often more accurate when describing relationships where one person exerts harmful control over another.

Muitos confundem um namoro tóxico com um relacionamento abusivo.

Tóxico vs. Maléfico: Maléfico: Implies an evil intent or a supernatural harm. You wouldn't call a chemical 'maléfico', but you might call a curse or a villain's plan that.

O plano do vilão era maléfico, espalhando um gás tóxico pela cidade.

How Formal Is It?

Formal

Neutral

Informal

Child friendly

Slang

Fun Fact

The root 'toxon' in Greek actually means 'bow'. So, 'toxic' literally started as 'of the bow', referring to the arrows shot from it.

Pronunciation Guide

UK /ˈtɔk.si.ku/

US /ˈtɔk.si.koʊ/

The stress is on the first syllable 'tó', marked by the acute accent.

Rhymes With

narcótico exótico antibiótico caótico hipnótico patriótico neurótico erótico

Common Errors

Pronouncing the 'x' as 'sh' (like 'lixo'). It must be 'ks'.
Making the final 'o' too strong. In most dialects, it sounds like a soft 'u'.
Ignoring the accent and stressing the middle syllable.
Pronouncing it like the English 'toxic' without the final vowel sound.
Nasalizing the first 'o' incorrectly.

Difficulty Rating

Reading 2/5

Easy to recognize because it is a cognate with English.

Writing 3/5

Requires attention to gender/number agreement and the accent mark.

Speaking 4/5

The 'ks' pronunciation of 'x' can be tricky for beginners.

Listening 2/5

Clearly articulated in most media due to the stressed 'ó'.

What to Learn Next

Prerequisites

perigoso ruim veneno mal saúde

Learn Next

nocivo insalubre prejudicial intoxicação saudável

Advanced

deletério mórbido pernicioso virulento pestilento

Grammar to Know

Adjective Agreement

O gás é tóxico. As nuvens são tóxicas.

Placement after Noun

Um ambiente tóxico (Not: Um tóxico ambiente).

Use of Ser vs Estar

Ele é tóxico (personality). O ar está tóxico hoje (temporary condition).

Acute Accent for Stress

Tóxico (Stress on the antepenultimate syllable).

X Pronunciation

Tóxico sounds like 'ks', while lixo sounds like 'sh'.

Examples by Level

Este produto é tóxico.

This product is toxic.

Simple subject-verb-adjective structure.

Não beba isso, é tóxico.

Don't drink this, it's toxic.

Imperative 'não beba' followed by the adjective.

O lixo é tóxico.

The trash is toxic.

Masculine singular agreement.

A fumaça é tóxica.

The smoke is toxic.

Feminine singular agreement.

Cuidado! É tóxico.

Careful! It's toxic.

Common exclamation.

Eles usam produtos tóxicos.

They use toxic products.

Masculine plural agreement.

Essa planta não é tóxica.

This plant is not toxic.

Negation using 'não'.

O ar aqui está tóxico.

The air here is toxic.

Use of 'estar' for a temporary state of the air.

Muitas tintas antigas são tóxicas.

Many old paints are toxic.

Feminine plural agreement with 'tintas'.

O mercúrio é um metal muito tóxico.

Mercury is a very toxic metal.

Use of intensifier 'muito'.

Precisamos evitar gases tóxicos.

We need to avoid toxic gases.

Plural noun and adjective.

Algumas algas podem ser tóxicas.

Some algae can be toxic.

Modal verb 'podem ser'.

O solo desta região é tóxico.

The soil in this region is toxic.

Prepositional phrase 'desta região'.

O veneno da cobra é tóxico.

The snake's venom is toxic.

Distinguishing the poison as toxic.

Não toque em resíduos tóxicos.

Do not touch toxic waste.

Imperative 'não toque'.

Este sabão tem um cheiro tóxico.

This soap has a toxic smell.

Describing a sensory experience.

Ela saiu de um relacionamento tóxico.

She left a toxic relationship.

Metaphorical use for relationships.

O ambiente de trabalho era muito tóxico.

The work environment was very toxic.

Describing a workplace culture.

Evite pessoas tóxicas na sua vida.

Avoid toxic people in your life.

Feminine plural 'pessoas tóxicas'.

A positividade tóxica pode ser prejudicial.

Toxic positivity can be harmful.

Abstract psychological concept.

Ele sofreu uma intoxicação por materiais tóxicos.

He suffered poisoning from toxic materials.

Noun 'intoxicação' related to 'tóxico'.

O comentário dele no Facebook foi tóxico.

His comment on Facebook was toxic.

Describing digital behavior.

A amizade deles tornou-se tóxica com o tempo.

Their friendship became toxic over time.

Verb 'tornar-se' (to become).

Não deixe o estresse se tornar tóxico.

Don't let stress become toxic.

Reflexive verb use.

O descarte inadequado de lixo tóxico é crime.

Inadequate disposal of toxic waste is a crime.

Legal/Environmental context.

A masculinidade tóxica afeta toda a sociedade.

Toxic masculinity affects the whole of society.

Sociological terminology.

Níveis tóxicos de chumbo foram encontrados na água.

Toxic levels of lead were found in the water.

Scientific reporting style.

É difícil mudar uma cultura organizacional tóxica.

It is difficult to change a toxic organizational culture.

Business context.

O filme retrata uma família extremamente tóxica.

The movie portrays an extremely toxic family.

Describing media/art.

Substâncias tóxicas foram banidas pela nova lei.

Toxic substances were banned by the new law.

Passive voice 'foram banidas'.

A exposição prolongada ao sol pode ser tóxica.

Prolonged exposure to the sun can be toxic (harmful).

Using 'tóxica' as a synonym for damaging.

O debate político tornou-se um ambiente tóxico.

The political debate became a toxic environment.

Political context.

A toxicidade dos agrotóxicos preocupa os ambientalistas.

The toxicity of pesticides worries environmentalists.

Noun 'toxicidade' and compound 'agrotóxicos'.

Eles analisaram os efeitos neurotóxicos da substância.

They analyzed the neurotoxic effects of the substance.

Technical prefix 'neuro-'.

A empresa foi multada por emitir efluentes tóxicos.

The company was fined for emitting toxic effluents.

Technical term 'efluentes'.

O autor critica a positividade tóxica na era digital.

The author critiques toxic positivity in the digital age.

Literary/Academic critique.

O veneno agia como um agente citotóxico potente.

The poison acted as a potent cytotoxic agent.

Medical terminology.

A retórica tóxica inflamou as tensões sociais.

The toxic rhetoric inflamed social tensions.

Describing speech/language.

Há uma linha tênue entre crítica e comportamento tóxico.

There is a fine line between criticism and toxic behavior.

Nuanced philosophical observation.

O solo estava saturado de componentes tóxicos.

The soil was saturated with toxic components.

Advanced vocabulary 'saturado'.

A mitigação de passivos ambientais tóxicos é urgente.

The mitigation of toxic environmental liabilities is urgent.

High-level corporate/legal terminology.

O ensaio desconstrói a noção de amor romântico tóxico.

The essay deconstructs the notion of toxic romantic love.

Academic 'desconstrói'.

A farmacocinética estuda como o corpo processa o tóxico.

Pharmacokinetics studies how the body processes the toxic agent.

Use of 'tóxico' as a substantive noun.

O discurso foi eivado de um nacionalismo tóxico.

The speech was tainted with a toxic nationalism.

Literary word 'eivado'.

A bioacumulação de metais tóxicos na cadeia alimentar é fatal.

The bioaccumulation of toxic metals in the food chain is fatal.

Scientific 'bioacumulação'.

Sua personalidade era um amálgama tóxico de inveja e orgulho.

His personality was a toxic amalgam of envy and pride.

Metaphorical 'amálgama'.

O governo negligenciou o monitoramento de gases tóxicos.

The government neglected the monitoring of toxic gases.

Formal political critique.

A hermenêutica do texto revela um subtexto tóxico.

The hermeneutics of the text reveals a toxic subtext.

Philosophical 'hermenêutica'.

Common Collocations

lixo tóxico

relacionamento tóxico

gás tóxico

ambiente tóxico

pessoa tóxica

resíduos tóxicos

substância tóxica

masculinidade tóxica

positividade tóxica

nível tóxico

Common Phrases

Isso é tóxico.

— Used to say something is physically or emotionally harmful.

Não coma isso! Isso é tóxico.

Cuidado, é tóxico!

— A common warning about a dangerous substance.

Não abra esse frasco. Cuidado, é tóxico!

Livre-se do tóxico.

— Used metaphorically to tell someone to remove bad influences.

Você precisa se livrar do que é tóxico na sua vida.

Amizade tóxica.

— A friendship that causes more harm than good.

Ela finalmente terminou aquela amizade tóxica.

Cultura tóxica.

— Harmful habits within a group or company.

A cultura tóxica daquela startup era famosa.

Comportamento tóxico.

— Actions that hurt others emotionally.

O comportamento tóxico dele afastou a família.

Efeito tóxico.

— The negative result of a substance or action.

O álcool tem um efeito tóxico no fígado.

Nuvem tóxica.

— A cloud of poisonous smoke or gas.

Uma nuvem tóxica cobriu a cidade após a explosão.

Produto agrotóxico.

— The full term for pesticides in Portuguese.

O Brasil usa muitos produtos agrotóxicos.

Vibe tóxica.

— Informal way to say a place has a bad feeling.

Aquele lugar tem uma vibe muito tóxica.

Often Confused With

tóxico vs venenoso

Use 'venenoso' for snakes/plants and 'tóxico' for chemicals/people.

tóxico vs intoxicado

This means 'poisoned' or 'drunk', while 'tóxico' is the quality of the substance.

tóxico vs tossir

Beginners sometimes confuse the sound of 'tóxico' with 'tossir' (to cough).

Idioms & Expressions

"Lamber o tóxico"

— Very informal/slang; to get involved with something very dangerous or addictive.

Ele está lambendo o tóxico ao sair com aquela gangue.

slang

"Veneno em conta-gotas"

— To do something toxic or harmful very slowly and subtly.

Ela solta o veneno em conta-gotas no escritório.

informal

"Respirar veneno"

— To be in a very toxic environment where everyone is angry.

Naquela casa, a gente respira veneno.

informal

"Plantar a discórdia"

— To act in a toxic way by starting fights between others.

Ele adora plantar a discórdia, é muito tóxico.

neutral

"Dar o sangue por nada"

— Often used in toxic work environments where effort isn't rewarded.

Eu dava o sangue por nada naquele emprego tóxico.

informal

"Sangue de barata"

— To have no reaction to toxic behavior directed at you.

Você tem sangue de barata para aguentar esse chefe tóxico?

informal

"Pisando em ovos"

— The feeling of being in a toxic relationship where you are afraid to speak.

Com ela, eu vivo pisando em ovos. É tóxico.

informal

"Lavar a alma"

— The feeling of leaving a toxic situation.

Sair daquele emprego foi como lavar a alma.

neutral

"Faca de dois gumes"

— Something that might seem good but has a toxic/harmful side.

A fama é uma faca de dois gumes, pode ser tóxica.

neutral

"Engolir sapo"

— To endure toxic treatment without complaining.

Eu cansei de engolir sapo naquele ambiente tóxico.

informal

Easily Confused

tóxico vs venenoso

Both mean 'poisonous'.

Venenoso is for biological venom (snakes/spiders). Tóxico is for chemicals and behavior.

A cobra é venenosa, mas o mercúrio é tóxico.

tóxico vs nocivo

Both mean 'harmful'.

Nocivo is more general (e.g., bad habits). Tóxico implies a poisonous or deep psychological harm.

Doces são nocivos, mas arsênico é tóxico.

tóxico vs insalubre

Both relate to health risks.

Insalubre is specifically for work conditions that are dangerous to health over time.

O local de trabalho é insalubre porque há gases tóxicos.

tóxico vs prejudicial

Both mean something bad.

Prejudicial means something that causes damage to interests or plans, not necessarily poison.

A chuva foi prejudicial para a colheita.

tóxico vs peçonhento

Specific biological term.

Peçonhento is for animals that have a specialized organ to inject venom (like snakes).

Escorpiões são animais peçonhentos.

Sentence Patterns

Este/Esta [noun] é tóxico/a.

Este produto é tóxico.

Não [verb] [noun] tóxico/a.

Não respire fumaça tóxica.

Eu acho que [person] é tóxico/a.

Eu acho que meu ex é tóxico.

Sair de um/uma [noun] tóxico/a.

Ela quer sair de um emprego tóxico.

O impacto de [noun] tóxico/a na/no [area].

O impacto de lixo tóxico no rio.

Devido ao ambiente tóxico, [consequence].

Devido ao ambiente tóxico, eu pedi demissão.

A toxicidade de [substance] é [adjective].

A toxicidade do chumbo é preocupante.

Sob a ótica da [field], o [concept] é tóxico.

Sob a ótica da psicologia, esse comportamento é tóxico.

Word Family

Nouns

Verbs

Adjectives

How to Use It

frequency

Very high in both spoken and written Portuguese.

Common Mistakes

A pessoa é tóxico. → A pessoa é tóxica.
'Pessoa' is a feminine noun, so the adjective must be feminine.
O lixo é venenoso. → O lixo é tóxico.
'Venenoso' is for biological venom; 'tóxico' is for industrial waste.
Pronouncing 'x' as 'sh'. → Pronouncing 'x' as 'ks'.
In 'tóxico', the 'x' always sounds like 'ks'.
Eu estou em uma amizade tóxico. → Eu estou em uma amizade tóxica.
'Amizade' is feminine.
Using 'tóxico' for 'annoying'. → Using 'chato' for 'annoying'.
'Tóxico' is much stronger than just being annoying.

Tips

Agreement

Always check if your noun is masculine or feminine. 'A relação' is feminine, so it must be 'tóxica'.

The 'X' Factor

Remember the 'ks' sound. Don't say 'tó-shico'!

Modern Usage

Use 'tóxico' to describe bad vibes or negative social media, it's very current.

Pesticides

In Brazil, 'agrotóxico' is the word everyone uses for pesticides in the food debate.

Social Impact

Be aware that calling someone 'tóxico' is a heavy label; use it wisely.

Accents

The accent on the 'ó' is mandatory. Don't skip it!

News Keywords

Listen for 'resíduos tóxicos' in environmental news segments.

Vowel Sound

The 'ó' is open, like the 'o' in 'hot' (American English).

Ser vs Estar

Use 'ser' for personality traits and 'estar' for temporary conditions like polluted air.

Labor Law

If you work in Brazil, learn 'insalubre' alongside 'tóxico'.

Memorize It

Mnemonic

Think of a 'Toxic' 'Taxi'. The 'x' in 'tóxico' sounds exactly like the 'x' in 'taxi' (ks). Imagine a taxi filled with green poisonous gas.

Visual Association

Imagine a skull and crossbones wearing a 'tóxico' t-shirt while arguing with someone to represent both meanings.

Word Web

veneno química relação perigoso saúde fumaça lixo pessoa

Challenge

Try to write three sentences: one about a chemical, one about a person, and one about a place, all using the word 'tóxico'.

Word Origin

From the Late Latin 'toxicus', which comes from the Greek 'toxikon', meaning 'poison for arrows'.

Original meaning: Specifically referred to the substances used to tip arrows to make them lethal.

Indo-European > Hellenic > Greek > Latin > Romance > Portuguese.

Cultural Context

Be careful when labeling people as 'tóxico' in person; it is a very strong accusation in Portuguese culture and can end friendships instantly.

The shift from literal to metaphorical 'toxic' happened almost simultaneously in English and Portuguese, making it a very modern shared concept.

Britney Spears' song 'Toxic' is well-known in Brazil and helped popularize the term. The book 'Relacionamentos Tóxicos' is a bestseller. Environmental documentaries like 'O Veneno está na Mesa'.

Practice in Real Life

Real-World Contexts

Science/Lab

substância tóxica
nível de toxicidade
reação tóxica
exposição tóxica

Relationship Advice

parceiro tóxico
sair de uma relação tóxica
sinais de toxicidade
amizade tóxica

Environment

lixo tóxico
nuvem tóxica
vazamento tóxico
solo tóxico

Workplace

chefe tóxico
ambiente tóxico
cultura tóxica
colegas tóxicos

Digital/Social Media

comentário tóxico
comunidade tóxica
usuário tóxico
conteúdo tóxico

Conversation Starters

"Você já teve que lidar com um chefe tóxico no trabalho?"

"Como você identifica se um relacionamento está ficando tóxico?"

"Você acha que as redes sociais são ambientes tóxicos hoje em dia?"

"O que você faz para se afastar de pessoas tóxicas?"

"Qual é a sua opinião sobre o uso de agrotóxicos nos alimentos?"

Journal Prompts

Descreva uma situação em que você percebeu que um ambiente era tóxico para você.

Quais são os limites entre um comportamento difícil e um comportamento genuinamente tóxico?

Como a 'positividade tóxica' afetou sua percepção de felicidade ultimamente?

Escreva sobre a importância de remover o que é tóxico da sua rotina diária.

Reflita sobre como evitar se tornar uma pessoa tóxica para os outros.

Frequently Asked Questions

10 questions

Yes, it is very common in modern Portuguese to describe someone who is emotionally harmful as 'uma pessoa tóxica'.

No. To say someone is drunk, use 'bêbado'. However, 'intoxicado' can sometimes refer to being under the influence of drugs or alcohol in a medical context.

The feminine form is 'tóxica'. For example: 'uma amizade tóxica'.

It is pronounced like 'ks', similar to 'taxi' or 'extra'.

Yes, it is the standard word for 'pesticide' in Brazil.

Rarely. It usually functions as an adjective. As a noun, it would mean 'a toxic substance'.

It is neutral. It can be used in scientific papers and in casual slang.

Venenoso is usually for nature (snakes); Tóxico is for chemicals and social behavior.

Yes, 'intoxicar' means to poison or to make something toxic.

It refers to the pressure to stay positive even in very bad situations, which can be harmful.