core/homeassistant/components/altruist/icons.json

{
  "entity": {
    "sensor": {
      "pm_10": {
        "default": "mdi:thought-bubble"
      },
      "pm_25": {
        "default": "mdi:thought-bubble-outline"
      },
      "radiation": {
        "default": "mdi:radioactive"
      }
    }
  }
}