I have used below code for add new attribute options in magento 2.
if (!$optionId) {
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();
$attribute_id = $this->getAttribute($attributeCode)->getAttributeId();
$languageValues[0] = $label;
$languageValues[1] = $label;
$attr = $objectManager->create('\Magento\Eav\Model\Entity\Attribute');
$attr->load($attribute_id);
$option = [];
$option['value'][$languageValues[0]] = $languageValues;
$attr->addData(array('option' => $option));
$attr->save();
// Get the inserted ID. Should be returned from the installer, but it isn't.
$optionId = $this->getOptionId($attributeCode, $label, true);
}
But its work only when attribute option is alphabet when i am trying with numeric value its not work.