Jenny Takeda was a normal girl with a normal family, normal friends, and a normal life in California. That all changed the day her boyfriend wound up comatose after kissing her. Tests at the hospital confirmed that she was the cause of his coma, and it was then that Norman Osborn, kidnapped her and jump-started her powers against her will. After returning home, her family was exposed to her for so long that they began to fall ill. Even her dog died after prologed exposure and contact with her. Then, thankfully, Hank Pym stepped in and invited her to the Avengers Academy, promising to work on a way to cure her condition, or at least help her regain control of it somehow.
Hazmat was created by writer Christos Gage and artist Mike McKone and debuted in Avengers Academy.
Jenny had a pretty priveleged life before developing her condition. She had a credit card, an iPad, and all the toys, along with a boyfriend. She lost it all when she almost killed him with a kiss, rendering him comatose. Norman Osborn lied to her, promising to help her understand and control her abilities, but only succeeded in making her condition worse. Jenny's current condition continues to shut her off from the rest of the world, as does her angry, standoff-ish personality, a trait that stems from her disillusionment with her inability to interact with others without her containment suit.
Major Story Arcs
When Hazmat and the others learn that there going to the Raft, she, Veil, and Mettle go down to Norman Osborn's cell to make him tell them how to reverse their powers so they can have normal lives again. Hazmat used a hidden EMP power she hid from the rest to cause the blackout. Osborn used his words well, and convinced the three that he could cure them later, though Hazmat very much felt like they blew their opportunity to kill him. The kids were scolded for leaving the rest of the group, but Mettle covered for the rest that it was fate that caused the blackout.
Lately, Reptil has been suspicious of Hazmat, but hasn't had any solid evidence that she was involved with the Raft incident. Reptil also tried to get Mettle and Hazmat to hook up as a couple, which humorously caused the two to be offended. After coming across the assault videos of Tigra being attacked by the Hood, Hazmat took the initiative and got Veil and Striker to track down the villain and attack him when he was powerless, videotaping the process as well. When they showed the tape to Tigra, she was furious, claiming the three were not Avenger material, and expelled the three from the Academy. The other teachers vetoed her expulsion, and they were allowed back, but Hazmat was to take anger management classes.
During her anger management, Hank Pym invited Leech to be with her for the day, allowing Hazmat to be able to live the day outside of her suit. She went home to see her parents, but was brought to tears when her parents were expecting her to be permanently fixed. On a trip to StaMord, the Cobolt Men attacked, but she was unable to fight back because of Leech's power drain. When Pym offered Leech to be with her biweekly, Hazmat turned the offer down, saying her lack of powers could get her killed, and that until a permanent cure is found, she will wear the suit and keep fighting.
As an attack by Korvac went underway, all the kids went through an alteration to become adults with their current minds to stop him. Hazmat started to freak out finding out she was still stuck in her suit. She along with Veil's help defeated Korvac, revealing that she had had the ability to generate anti-matter in her future self. After returning to her normal self, Mettle came in to comfort her. At first she was stubborn, but she then revealed her pent up sadness, and the two cried about being stuck in their current states for the foreseeable future.
During Prom, Hazmat lashed out at Veil for trying to get her together with Butterball, asking why she should be stuck with ugly potential boyfriends. Mettle overhears this, and smashes a statue in the hallway. Hazmat comes out and apologizes, and the two open up with one another, being honest about what they think of the other. Hazmat then proposes that they probably should try dating.
Later during Fear Itself, Hazmat and Mettle become boyfriend and girlfriend. The when the team returned for fight the villains, Mettle had a talk with Hazmat about their experiences in the battle. He later said he killed some people which bothered him. She then asked Veil to help Mettle since she experienced a similar encounter. As Titania and Absorbing Man terrorize the Infinite Mansion, Hazmat, with Striker and Finesse, start to outsmart them, having her pretend to be switching sides as well as exploding like a nuclear bomb to slow them down. While stuck on the Infinite Mansion, which was slowly growing to crush Chicago, Finesse suggest that they set the building to self destruct. Hazmat choose to stay behind, as Mettle didn't want her to die alone. Before they confronted the two Worthy, they gave a kiss, and began to fight the two behemoths. Hank Pym busted into the building just in time to save the the two students.
Hazmat, along with the other four kids went to the West Coast Manor for the new semester. Initially afraid that she and the others would be replaced by the new students, because of the fact that they were still somewhat unstable and that Norman Osborn was responsible (not to mention how she, Veil, and Mettle tried to kill him on the Raft), she manages to get them worked up, and a fight ensues between the teachers and the "first year" students. Later, desperate to be with Mettle, Jennifer tries to have sex with him before they get sent away. However, before they can follow through with her intentions, she realizes she can't because she is too afraid, after the last time she tried to have sex with her now ex-boyfriend, who wound up in a coma after a simple kiss. The kids later find out they are staying, much to both Hazmat and Mettle's relief.
When Hazmat brings Mettle to talk to X-23 about killing, the Reptil, who is possessed by his future self, comments that X-23 could steal Mettle from her, thus putting a wedge in Hazmat's and Mettle's relationship. Hazmat and Mettle continued their relationship for the entirety of the series, eventually consummating it in the final issue.
Along with 15 other teenage heroes, Hazmat was kidnapped by Arcade, and placed in an arena in which they will be forced to fight to the death until only one remains. To show the heroes that he was serious, Arcade moves to kill Hazmat. To save her, Mettle steps forward, allowing himself to be killed to save the girl he loves.
Jenny can produce radiation and other toxic substances from her body. All of her body's tissues and fluids are toxic including her sweat, saliva and even breath. She is also completely immune to the toxic substances she can generate, and has even demonstrated the ability to absorb the hazardous substances she generates, though it is unknown if she can absorb other toxins and forms of radiation that she has not created. She later emits an EMP that the instructors at the Academy have no idea she is capable of producing. This could likely be explained in that, for robots, cyborgs, and electronics in general, an Electo-Magnetic Pulse is quite possibly the most toxic, harmful thing they are vulnerable to, if the only thing.
During Fear Itself, Hazmat displays an explosive power, where she explodes like a nuclear bomb and absorbs all of the radiation being released in a single move. It is possible that Jennifer possesses the ability to incite explosive reactions by generating the proper toxic elements required to create a nuclear bomb, or any other form of explosive. Whether this means that she is gaining more control over her abilities of if she did this unconsciously is unknown at this time.
In the wake of the student's battle with Korvac, it was reviealed that, at some point in the future, Jennifer has gained enough control over her powers to the point where she is able to generate and emit a concentrated burst of anti-matter energy potent enough to defeat Korvac.
Hazmat is very bitter about her condition, and her dim outlook on her situation and that of the others affected by Norman Osborn's monstrous experiments leads to her being bitingly sarcastic at times. She tends to be the quickest to snap at others and most likely to downplay the instructors. She seems to bond most with Veil and Mettle, since both of them are at risk of either dying or remaining in an inhuman state for the rest of their natural life because of Norman Osborn's extensive tests to push their powers to their limits. She appears to be a "tsundere" however, which is a Japanese literary term/character trope that refers a person who is initially cold but is very loving and gentle once they warm up to someone. Recently, Jennifer has entered into a relationship with Mettle, who's iridium metal body allows him to touch her and be around her without suffering any ill-effects from her abilities. For now, its seems as though their relationship is a platonic one, but whether or not that is subject to change in the future is unknown.