Washington becomes briefly the world’s most polluted major city on July 4, according to IQAir data reported by multiple outlets. The spike is linked to a large Independence Day fireworks display promoted by the Trump administration and organized through the Freedom 250 effort. The fireworks are conducted by Pyrotecnico, which is described as aiming to break a world record by launching about 850,000 fireworks within roughly 40 minutes. Experts cited by one outlet warn that concentrating such a high number of fireworks in a short period can pose serious health risks. Both reports note that the holiday coincides with a record-breaking heat wave that disrupts typical July 4 events, including parades, block parties and barbecues. While the fireworks are presented by officials as “awesome” in one account, the reporting focuses on the measurable air-quality impact shown by IQAir and the public-health concerns raised by experts. The sources do not indicate that authorities issue a single uniform assessment beyond the pollution reading and the described health risk warnings.