@glasspusher
California: 40,000 people ordered to evacuate over chemical leak fears
https://www.theguardian.com/us-news/2026/may/22/california-orange-county-chemical-tank
There are literally two options left remaining: one, the tank fails and spills a total of about 6- to 7,000 gallons of Methyl methacrylate into the parking lot in that area. Or two, the tank goes into a thermal runaway and blows up, affecting the tanks that are around them that have fuel or the chemicals in them as well
Garden Grove is a city in northern Orange County, California, United States. The population was 171,949 at the 2020 census. State Route 22, also known as the Garden Grove Freeway, passes through the city in an east–west direction. The western portion of the city is known as West Garden Grove.
https://en.wikipedia.org/wiki/Garden_Grove,_California
The principal application, consuming approximately 75% of the MMA, is the manufacture of polymethyl methacrylate acrylic plastics (PMMA).
In terms of the acute toxicity of methyl methacrylate, the LD50 is 7–10 g/kg (oral, rat). It is an irritant to the eyes and can cause redness and pain.[17][18] Irritation of the skin, eye, and nasal cavity has been observed in rodents and rabbits exposed to relatively high concentrations of methyl methacrylate. Methyl methacrylate is a mild skin irritant in humans and has the potential to induce skin sensitization in susceptible individuals.[19][20]
https://en.wikipedia.org/wiki/Methyl_methacrylate
Poly(methyl methacrylate) (PMMA) is a synthetic polymer derived from methyl methacrylate. It is a transparent thermoplastic used as an engineering plastic. PMMA is also known as acrylic and acrylic glass and by the trade names and brands Crylux, Walcast, Wanjiale, Hesalite, Plexiglas, Acrylite, Lucite, PerClax, and Perspex, among several others (see below). This plastic is often used in sheet form as a lightweight or shatter-resistant alternative to glass. It can also be used as a casting resin, in inks and coatings, and for many other purposes.
It is often technically classified as a type of glass in that it is a non-crystalline vitreous substance, hence its occasional historical designation as acrylic glass.
7000 US gallons of liquid methyl methacrylate (MMA) weighs approximately 24,845,958 grams (or about 24,846 kilograms).
Adult laboratory rats typically weigh between 225 and 520 grams
10g of MMA will kill a rat.
there is enough to kill 2.484,596 rats
While LD50 values for rats and mice are often the baseline numbers used in toxicology, you cannot assume a rat's lethal dose will directly equal a human's.
https://www.canada.ca/en/health-canada/services/environmental-workplace-health/occupational-health-safety/workplace-hazardous-materials-information-system/hazardous-substance-assessments/methyl-methacrylate.html
apart from it being explody, it could be worse.
Complete combustion of 7,000 US gallons of methyl methacrylate releases roughly 2,100 gigajoules of thermal energy.
For context, this is equivalent to the explosive yield of about 0.5 kilotons of TNT
The atomic bombs detonated during World War II had yields ranging from roughly 15 to 21 kilotons of TNT
On 4 August 2020, an estimated 2.75 kt of ammonium nitrate exploded in the Port of Beirut, Lebanon.
These data were analysed to make a preliminary estimate of the TNT equivalence of the explosion, with a best estimate of 0.5 kt and an upper limit of 1.12 kt.
https://ui.adsabs.harvard.edu/abs/2021ShWav..31...95D/abstract
https://en.wikipedia.org/wiki/2020_Beirut_explosion