An unnamed man's gut hangs out as he sunbathes. Robyn remarks of him, "roasting like a pig on a stick".

The title character briefly appears nude in the first episode (this scene also appears in the first season intro), however she is behind some boxes and nothing is seen below her shoulders. She giggles awkwardly and asks her sister to please bring her some clothes.

Some brief romantic scenes with kissing, lingering stares, but nothing overtly sexual in nature.

Some boys appear shirtless in a pool party scene, but no revealing bathing suits, only swim trunks and one-pieces.

In one episode a doctor threatens to give Louis Driscoll a "testicular spike".

Some kissing scenes. Alex's face glows yellow after a passionate kiss with Hunter.

Dave wears a hospital gown and nothing else in the "Senora Garcia" episode. So does Louis in one episode.

Some girls wear short skirts.

Some characters wear crop tops, tube tops, shirts revealing low cleavage, and low-cut jeans.

Barbara and George wear nothing but bathrobes at a spa resort in one episode. Danielle Atron mocks George about the trip but is then seen having to go there herself with some investors, in the same bathrobe as Barbara and George.

Alex says Hunter is "in love with Danielle Atron".

Louis develops a strange crush on Annie; this is not overtly sexual, though he does express romantic intentions.

No serious violence for the most part. The occasional bit of schoolyard fights/bullying, and some scenes of mild injury, but nothing severe. No gore.

Hunter's father is said to have been killed in what's implied to have been a murder by drowning during a fishing trip.

Alex often worries aloud that if the chemical plant caught her, they'd "cut her up". In various episodes her fears are proven to have some backing. When Vince catches a monkey infected with GC-161 named Oscar, he excitedly says to Danielle, "we'll have to cut it open!" Danielle says in one episode that she wants to see the effects GC-161 has on cells and organs.

In the 4th season, the day Hunter is first introduced, Louis Driscoll mentions "fetal pig dissections" and brings in a live pig on a leash "to make a statement". The pig isn't harmed.

There are disturbing mentionings of scientists being killed off in the 1970's under mysterious circumstances ("BMX" episode) and Chappy the hobo is knocked unconscious by Vince.

Danielle Atron is rumoured to have been the victim of child abuse during a Halloween-themed episode.

An unnamed woman suffering from heat stroke falls unconscious; her body is seen on the ground on-screen briefly.

An elderly teacher trips and falls on top of a man.

A hamster dies and Robyn falls into grief over it.

A girl is abandoned at a demolition site and nearly killed.

A man cries out in pain when a radio is played loudly over his ears.

Vince is mentioned to have no friends and to have been frequently beat up in school.

Kelly is chased by a moving construction vehicle, and Alex and Ray laugh at her instead of helping her.

A doppelganger of Alex knocks Ray over by zapping him in the chest with electricity.

A boy is incapacitated with electricity in a truck.

A boy is trapped under a concrete pipe.

Alex's foot is squished under a dump truck.

A rabbit "morphs" into a puddle, and much to Lars' horror, the rabbit can't reform itself and is permanently stuck this way. He fears that humans who eat the chemical will end up this way, too.

Lars tries to blow up and kill George Mack with an improvised explosive. George survives.

Alex mentions pulling out a frog's intestines with tweezers.

A morbidly obese girl shows adverse health issues after trying a drug.

A girl is chased home and threatened with hockey sticks.

A man tells Vince that he'll "burn you so bad your teeth will melt".

Alex frisks a woman and threatens Vince with a baseball bat.

Vince falls from a ladder and injures his neck. He then later gets electrocuted after accidentally placing his hand on a bug-zapping machine that kills insects.

Lars and an unnamed chemical plant employee both receive electric shocks that mildly impair them for a temporary period.

A man falls into a pile of hay and horse manure.

Some instances of belching; Alex belches out visible bubbles in one scene, and in another, Dave lets out a loud burp after eating a bunch of food. Vince and Danielle read a statement about a young boy who belched loudly and then remarked "super burrito".

The word "ass" is said in the 4th season (the episode titled 'Ashley').

Danielle Atron frequently puts down her employees, calling them incompetent, stupid, moronic, etc.

Various episodes feature bullying. The bullies call their victims childish words like "dork", "geek", "wimp", "nerd", "freak", "loser", "stinker", etc.

In one episode, a girl several years younger than Alex calls her best friend "bubblebutt".

Mild name-calling ("pig", "creepy/creep", "fat", "ugly").

A boy with apparent autism is referred to as "creeper" by the other students.

Danielle is seen drinking what appears to be a martini.

Danielle Atron tries to sell the chemical that mutated Alex as an addictive wonderdrug that can supposedly make people lose weight without dieting or exercise; it's stated that she has very little emotion or regard for who'll be taking it and getting sick from it. She pays off an FDA member to allow the near-untested drug to be sold on the market after showing a committee some Kodachrome slides of false results.

Alex is drugged with a reactive chemical at a carnival and suffers physical side-effects as a result.

In the last episode, Lars and Danielle share wine and cigarettes as they plan to bomb the chemical plant.

Lars roofies an FDA official's drink with a drug, and then puts the unconscious man in a women's dress, abandoning him in a public park where he's later said to have been discovered running around in a disoriented state, still wearing the dress.

Annie leaves for college in a quite tense, emotional episode. Alex cries and hugs her.

Alex often gets into peril but always escapes unharmed. Some mild suspense.

The final episode is surprisingly intense and emotional. The scene where Alex finally tells her parents about the accident is incredibly sad.

In the 3rd season, Vince begins to go slightly crazy and frequently has outbursts, acts erratic and stalks Lars and Danielle.

Danielle killing Hunter's father (presumably he was drowned) may upset some viewers.

Children may find the character of Danielle Atron disturbing, especially in the later seasons (it is revealed that she is willing to murder people).

Robyn is a depressing person and frequently mentions death, apocalyptic ordeals, suicide, etc.