Update, Wednesday 6.45am: OPINIONS are divided over whether swimming at Lennox Head's tea-tree lake is making people sick.
The debate started after a number of people, including at least 20 children, reported falling ill with vomiting and diarrhoea at the weekend.
There are fears the hot weather may have sparked an outbreak of blue-green algae.
Ballina Shire Council is currently doing testing at the site.
Will you still swim at Lake Ainsworth?
This poll ended on 17 January 2018.
This is not a scientific poll. The results reflect only the opinions of those who chose to participate.
On The Northern Star's Facebook page, Monica Wilcox wrote: "If half the people who are in the lake at this time of the year, get out of the lake and go to the loo, things would be better for people and the lake."
Others also blamed poor hygiene of swimmers.
Allison Sneath: "More research and questions needed ie are these children camping at the caravan park and are they washing their hands correctly after using bathrooms? Come on, it's not the lake, it's poor bathroom hygiene."
But Natalie Charity said she swam there on Sunday and did not get sick at all.
"Family have been a few times over the past couple of weeks and have not been sick either," she wrote.
Dennis Pickford said: "Bit of common sense would stop people getting sick It's a stagnated body of water, don't put your head under and don't get any water in your mouth."
Update 3.15pm: GASTRO-like symptoms have been linked to swimming at Lake Ainsworth by scores of residents who were at the popular watering hole over the weekend.
Ballina Shire Council and NSW Health have confirmed there have been no reported cases of illnesses attributable to swimming at the in the tea-tree stained dunal lake.
But many who have fallen ill after a dip are struggling to pinpoint another cause for their illness.
Lisa Jones, of Lismore, is among those who have battled a violent bout of vomiting and diarrhea over the weekend.
Ms Jones said just over 24 hours after her "good soak" at the lake on Saturday she was struck down with vomiting for two days.
"I feel like I've been hit by a car," The Northern Star employee said.
"In fact, if I didn't live alone I would have considered someone driving me to emergency."
Still fighting to overcome the illness, Ms Jones said she had booked in to see her GP to determine the cause of her sickness.
Update 12.25pm: HEALTH authorities have not received any notifications of people with illnesses attributable to swimming in Lake Ainsworth.
This is despite plenty of concerned lake users posting on social media about their plight with sickness following a swim at the popular lake at the weekend. But others commented they were fine after swimming at the lake.
Lake Ainsworth was a popular place to be as people tried to escape the scorching temperatures as well as to protest proposed changes to the precinct.
The Northern NSW Local Heath District also confirmed that presentations at Ballina District Hospital's emergency department on the weekend were at normal levels for this time of year.
Chief executive Wayne Jones said there had been "no records of presentations linked to swimming in Lake Ainsworth".
Ballina Shire Council's acting group manager for environmental health, Kerri Watts, said the lake was being tested today and tomorrow as part of ongoing water monitoring at the lake.
Since Saturday, Ms Watts said only four calls had been made to the council concerning sickness linked to swimming in the lake.
She said "small flecks of green material" can be seen in the lake when there is elevated levels of blue green algae.
When the conditions are still, a green blue coloured scum appears on the water's surface.
The council is continuing investigations into concerns raised about the lake.
Original story 10.45am: FEARS of blue-green algae contamination at a popular Lennox Head lake have sparked safety concerns after more than a dozen kids fell ill after swimming.
Ballina Shire Council confirmed a complaint was lodged by Goonellabah father, Tony Ellem, who said about 20 children, aged between 7 and 12, became unwell 24 hours after his son's birthday party at Lake Ainsworth last Friday.
Acting group manager for development and environmental health, Kerri Watts, said the council had launched an investigation to confirm whether blue-green algae in the lake caused the children to fall ill.
Blue-green algae can result in skin irritation and it can cause respiratory distress and vomiting and if the water is ingested.
Mr Ellem said all three of his sons, aged 13, 11 and 9, "chucked it out at home" on Saturday and were "pretty wiped out" all day Sunday.
But other kids at the party were much worse, Mr Ellem said, after contacting parents at the party to warn them about the illness.
He said some parents told him they took their children to the emergency department over the weekend.
"Some of the other kids were a lot more severe," Mr Ellem said.
He said food poisoning was "ruled out pretty early" after speaking with other parents about the condition of their children, who he said didn't eat any food provided.
The hot temperatures over the weekend was what Mr Ellem said may have caused a spike in blue-green algae (cyanobacteria) levels in the lake.
The NSW Health website states drought and increased temperature in the summer may result in an increase in cyanobacterial algal blooms.
A number of concerned parents have shared their stories on social media about their children falling ill after a swim in the lake.
Renee Turner put a call out on Facebook to find out if anyone else had come down with " a tummy bug" after swimming in the lake, citing her son, 13, had become sick after a dip at the lake recently.
No restrictions on recreational use apply at the lake after testing on January 10 confirmed cyanobacterial biovolume was at safe levels.
Ms Watts said there had been no blue-green algae alerts over the summer.
In September and October last year, Ballina Shire Council issued amber alerts for increased presence of cyanobacteria.
The lake was closed for swimming and other recreational use in February 2014 and January 2013 after major blue-green algae outbreaks sparked a red alert.
A red alert means water users are prohibited from swimming in contaminated waters and local and health authorities should be contacted to assess risks to water users.
Lake users should note any signage at the site and should report any sign of algae which may appear like a green paint spill on the surface of the water are asked to call Ballina Shire Council's Environmental Health Unit, 6686 1210.
Update your news preferences and get the latest news delivered to your inbox.