But the gun club, Youthtown and a health expert say the discovery of lead - though it warranted investigation and improvements to practices - did not mean there was a risk to health. The youth centre said all activity areas had been tested and found to be safe to use.
At least 10 gun club members were found to have high levels of lead.
A member said he saw a doctor after coming down with a series of bad headaches and feeling drowsy.
"I just felt miserable and grotty and I went along to the doctors and got a blood test. The doctor told me the test came back with high lead levels - which is a notifiable disease."
The member said he could not understand how that could be the case until his doctor asked about his weekly schedule.
"I told him I went to the shooting range every Friday night. He straight away wanted to know where we did the shooting. Other people had also contacted their doctors and they were notified, and so it was becoming more general."
The member was told to stop going to the range immediately.
"Lead is accumulative. But it will eventually work its way out of your system if you get away from whatever's causing it. I'm fine now. I stopped going straight away. But it was quite bad for a time."
Youthtown asked the shooting club to fix the ventilation problem in order to continue renting the basement level. The parties could not reach an agreement, so the shooting range closed in September.
Youthtown chief executive Keith Thorpe said all areas had been tested, including the pool storage area.
"I can show you the results of the tests that show the areas that are used by staff and kids for activities are completely safe."
Two supervisors at Hilton Brown Swimming, which runs classes at the pool, said they had no idea there had been any concerns about lead.
CSI secretary Wayne, who asked for his surname not to be printed because of security concerns relating to his guns, said when volunteers were asked to test their blood two years ago, 10 or 11 were found with lead above the notifiable range.
This led to changes in practices, such as wearing masks while cleaning, he said. Lead levels among everyone who had been tested dropped significantly in three months.
Chief shooting range inspector Peter Miles said lead poisoning was common at indoor ranges.
Health expert Dr Virginia Hope, now with the Institute of Environmental Science and Research, said a notifiable level of lead was a trigger to test for the toxin's source. "That may not be a clinically important level. They're levels which require further investigation."
A spokesman for the state agency that oversees occupational safety said public health officials had been involved. Youthtown had taken care of the issue "in-house".
