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DALLAS (CBS 11) — With a new week about to begin, some Dallas parents say they’re not sure their children’s school is safe for them to go back to class Monday.

Recent illnesses at Lakewood Elementary have prompted new fears about an old problem that some worry may have returned. The district is monitoring environmental quality inside the school, and it’s been collecting data all weekend. So far officials say they haven’t found anything out of the ordinary, but some parents worry what they don’t know may be hurting their children.

With two more children set to start kindergarten at Lakewood Elementary in a couple of years, Gretchen Darby worried when her first-grader started complaining about headaches, stomach aches and fatigue a couple of weeks ago.

“It just kind of took me back to last year when my daughter was in kindergarten, and we had the carbon monoxide scare, and I was just really hoping that wasn’t the situation again,” Darby said.

In March, emergency officials had to evacuate the school and keep it closed for days after they found high carbon monoxide readings following several illnesses. Since then the school has made repairs and installed a carbon monoxide monitor. That’s why Darby didn’t think much of her daughter’s latest illness at first.

“But then when I started to hear from other parents that very similar symptoms were happening in their children, and then I started seeing a lot of buzz from parents on social media about exactly the same thing,” Darby said.

In response to the latest round of symptoms, Dallas ISD began monitoring the air quality inside the school, including carbon monoxide levels. The district insists it’s found nothing wrong, but Darby worries the problem could be something beyond what’s being monitored and would like to see more extensive testing. She’s hoping whatever the problem is, it only goes back as far as these recent illnesses.

“But if it’s been going on for longer and the long-term exposure has been in any way harming our children and their development, that’s really, really scary,” Darby said.

At this point Darby says she’s leaning toward keeping her child home from school until she learns more about what’s causing the illnesses. Dallas ISD says the school will be open Monday as scheduled.

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