Air monitoring for hexavalent chromium or chromium 6 and other toxic air contaminants in Paramount has been on-going since late 2013 when the South Coast Air Quality Management District (SCAQMD) responded to community complaints of metallic odors thought to be coming from a metal forging and grinding operation in Paramount. On September 13 2021, monitoring was discontinued by AQMD and restarted on November 18, 2021 by T&B, a contractor for the city of Paramount.

Hexavalent chromium, also known as chromium 6, is a metal used in certain industrial processes, such as metal plating, leather tanning, and welding. While exposure to chromium 6 generally does not lead to immediate health symptoms, breathing chromium 6 at high levels over many years can cause or worsen breathing problems such as asthma, and cause irritation to the nose, throat, and lungs. Chromium 6 is also a known human carcinogen, and exposure to high levels over many years may increase the risk of lung and nasal cancers.

The Paramount investigation is still ongoing and is being monitored. If the level is above 1ng/m3 for three consecutive readings (SCAQMD’s action level), SCAQMD will take enforcement measures. For 24-hour sampling data from Trinity Consultants, a contractor for the City of Paramount, please visit their site.

Figure 1 below shows the average hexavalent chromium levels in the air for each month in 2026.

Figure 1

You can find additional information on the South Coast AQMD on-going air monitoring activities.

Local and state agencies have worked to identify facilities that produce chromium 6, and to lower the amount of chromium 6 that they release. Since November 2016, DPH and SCAQMD have issued Public Health Directives and Orders for Abatement to businesses in Paramount and North Long Beach related to chromium 6 emissions and/or odors. These facilities include Anaplex, Aerocraft, MattCo Forge, Press Forge, Weber Metals, Carlton Forge Works, and LubeCo. The SCAQMD has been developing and implementing new air quality rules to regulate chromium 6 in metal processing facilities. In addition, the City of Paramount has adopted revised zoning rules for metal processing operations to reduce emissions.