The Consumer Council warns that fluorescent sticks, often used at concerts, parties and religious festivals, contain toxic substances that can be harmful. Some sticks, if leaking or snapped open, can release chemicals that burn the skin and irritate the eyes, and cause coughing, vomiting and dizziness if inhaled. The council also warns that do-it-yourself electronic blood-pressure monitors can give false readings. Tests also showed some models gave normal readings although the users had blood pressure problems. Consumers should also be wary of some jewellery shops that refuse to honour refund agreements for gold ornaments, the Consumer Council advises.