Costco Gas Hours. On weekdays (Monday to Friday) Costco gas hours is 6 AM to 9 PM . On Weekends (Saturday and Sunday) Costco gas open 1 hour late and close 1 or 2 hours before their usual timings and its timing is 7 AM to 8 PM on Saturday and 7 AM to 7 PM on Sunday. Costco Gas stations are normally closed on some national holiday and religious holiday.
1 BPA does indeed form in the mouth after some dental sealants and fillings are applied. BPA can be found in the saliva three hours after dental work is completed. It's not at all clear whether this poses a health risk.  A quick wipe and rinse of the completed dental work vastly decreases whatever risk there might be.
While the tooth sealant covers teeth like a blanket and protects them from plaque, the purpose of sealants is not to replace a consistent oral care routine of twice-daily toothbrushing and daily flossing. Brushing and flossing are still the best ways to remove plaque and help prevent tooth decay.